Having just replaced the clutch disc in my 1-ton Flatbed, IF you were to put anything in I would also suggest a MUncie 4.

You get that low granny gear for grindin out torque for towing and hauling. Then your standard 3 speeds as well.

I will say that it IS a beast.

As I stated I just replaced the clutch disc. For a while I had thought that the noise I was hearing under the floor board was the TO bearing. Then one day it decided to go out completely good thing I was already getting the full package since we got it used.

Well I got under there and as my buddy was unbolting the starter on his side he remarked about the starter needing shims.

As I was starting to undo the E-brake cable I was looking up into the tranny to engine portion and low an behold the whole drivers side of the tranny was a full half inch off the engine.

Gee wonder why the starter needed shimming? Hmmmmm...

I figure the previous owner had clutch work done to it and the fools either lost bolts or didn't make sure to put some LocTite on em and they vibrated out.

Anyway got it out and found that I only had to replace the disc. Replaced the TO bearing and Flywheel even though not entirely needed. The flywheel had some dinged up teeth but nothing too bad.

I just thought you might want to know that IF you were to go with the Muncie 4 that it's one hell of a tranny. No leaks in mine whatsoever undid the the inspection/fill bolt and checked it was up to snuff but I drained and refilled that as well.

Just make sure that your bolts have keepers or you use LocTite on em. Vibration is a beast. Mine's on a 350. Yours will definitely rattle out the most stubborn of bolts if they aren't secure being a 454.