Geoff Weeks

In that case, the A-6064 is what you want. You are likely to need a hanger at the back end of the transmission if you get away from the nodal mount for the rear engine mount.
I learned quite a lot doing the research on your issue. I had always thought that the bells with the lower holes were for push clutches, and now know that they can be or can be for lower pull clutches depending on placement of of holes.
I hope you now have enough info to carry your project to fruition. 

Every truck junkyard has a ton of mounts. If you stick to the same brand, you can keep your 5th wheel and just replace the mount.
 Otherwise you can buy the whole thing.
 They are not "adjustable". The mount determines the height off the frame.

Engine coolant thermostat 180-190 deg F, Fan switch, 205-210 deg F.
 Often people who don't understand, use a low 160 deg thermostat to try and solve an overheating problem, it will not!  the engine thermostat only sets the MINIMUM temp the engine can run at, above that the thermostat has no effect. 
160 deg thermostat and fixed fan, tells me someone is having over heat problems and isn't dealing with the real problem but trying to "get by' without fixing the real problem, which it likely to be the radiator.
 The radiator only has to drop the coolant temp 10 degs F at full load, if it can do that, the engine will never over heat. The outlet of the engine at 190 (thermostat temp) and the inlet back to the engine at 180 deg. When really working hard the outlet will be 200 and the return 190, when there isn't enough air flow to drop the coolant that 10 degs the fan kicks on at 15 deg above thermostat temp or so.
 Overheat alarm is often set at 220-225 deg (may be higher on the newer engines.)
Radiators can be expensive, but often they are the true fix. I have spent more on a radiator than I did on an engine overhaul kit ($2150 for a radiator, $1500 for an overhaul kit).

I believe a few months ago Watts was selling the complete kit. I know Red Dot also makes a kit for the R model.

https://speedometercablesusa.com/cables_and_housing_assembly.html
Just one of a few places that come up on a search.

In the Yoos brothers post you can see the bell and trans clearly
 

Pyro's thrermocouple  are placed down stream of the turbo so if the tip fails (burns off or breaks) it doesn't take out the turbine wheel. 1300deg F is considered the max temp, ahead of the turbo, with 1100-1200 post turbo.
 Some manifolds have plugs pre turbo for diagnoistic purposes but for running full time, I have only seen them after the turbo.

Do as it says, fill to bead, the bottom will be full also. If you don't have enough oil in it, it doesn't clean the air. Oil Bath filters restriction remains constant over the service interval. They clean better then a "new" paper filter, but slightly less than a used paper filter that has some time on it.
 As long as they are serviced at regular intervals they last a life time.
 Some of the buses I worked on had oil baths the size of a waste basket and took more than a gal of oil.

Not much to hurt you taking one apart, no real stiff springs ready to jump out at you. That is/was a real common model, The name escapes me at present. X3500? Anyway, not saying you can't hurt yourself if you really tried, but the most likely way would be dropping it on your foot! Remove the bolts and pins, there are two big pins that pass though the casting. Pay attention to how it comes apart and put it back together the same way. Getting the bolts to come out is the hardest part of the job.

Reading back through this thread, I see a couple questions that were never answered.
The Engine family that is the medium K's (BLD) at one point COULD be fitted with a Mag. I have seen it mentioned in literature but never in person.
 The early (wet liner) version of the engine had either a gear driven generator and distributor driven off the back of the generator, on the left side of the engine or a mag. This was a common practice in the 20's. The mechanical fuel pump that is on the left side in the K's was on the right side on the early engines with a pushrod that ran across the block to the cam on the other side. If you pull the generator mount off a BLD there is a casting hole in the block behind it in the shape of a fuel pump mount, but not machined out. Wetliner engine are easy to spot due to the lack of core plugs in the side of the block, as core sand could be shaken out through the bore openings. (Like most wet lined engines)
 This design lead to a problem when gear drive generator/distributors were abandon in the later 30's. Where to you put a distributor on an engine that didn't have a directly driven distributor designed in from the get go? The answer is one of the distinct visual ques  of the engine family, namely a distributor mounted high over the valve cover. When the engine was designed, it had the oil pump drive off the inside of the cam, which left no room to mount a distributor directly on the oil pump drive. Most engines drive the oilpimp from the outside of the cam, allowing for enough room to mount a distributor. They extended the drive all the way up to the top of the valvecover, and mounted the distributor there. This lead to problems later in the 50's when installed in cabover trucks. But that is a story for another day.
 The same basic engine lasted until the late 60's early 70's.  It wasn't, however exported to the land down under which used a AG version of the the small 6 in their trucks of the size that used the BLD/BD up here.
 The HiTorque rear brakes are another issue. They have a special cup on the small piston with a protrusion that sits in a recess in the piston. As far as I know these cups are not available anywhere unless someone stumbles on NOS. To rebuild you must fill the recess with epoxy (to make a flat surface) and use a common available cup.  Not sure what the thinking was on the recess, but seams to function fine without them.
 Like all IHC designed 6's it used a gear driven cam, a remote (from the oil pump) relief valve that can be a problem if someone tries to replace the oil filter adapter or valve adapter if the engine has no filter, with one from a later engine.  Early engine had a bypass oil filter and the later (50's and up) re design had a full flow filter, but they are not interchangeable.
 More info than most will be interested in I bet.