I took on a different project I'm afraid. I've installed a Duramax/Allison into the rear of a FMC motorhome. I used the dash cluster and steering column from the 2006 Silverado. Used all three computers as well as both fuse boxes from the roll over donor. I have all the steering wheel controls working as well as automatic lights, the donor trucks wiper motor replacing the two OEM FMC motors with stalk controls like the chevy truck had. Installed disc brakes all around with a hydroboost up front-really ,really tight fit. Had to build a bell crank to turn the booster sideways along with the master cylinder, even had to remote mount the master reservoir because of the limited space. Liquid to air intercooler, 370 amp secondary alternator Lithium batteries, increased fuel tank size, Led headlights as well as sequencing tail lights. Running and driving, just working out some issues like cruise control.
Sourced a rear for the GMC that can hold the power vs the Dana 70 I had in the pusher. I didn't like the flipped shortened rear and was concerned with its capacity. The clock is ticking I'm afraid and don't know if the pusher will get finished. I'll be 76 next month (Lord willing) and find it takes much longer to get 'stuff' done now. And with a move back to Nevada looming.....