Great work Regal! Looking at your 4310, it looks similar to my 4200, which shares the same body and frame as the 4300 and 4400, so I'll bet your parts will work on a 4200 - 4400, 4210 - 4410.
The worst part is sealing up the gaps at the back by the 3PH and by the cowl and brake pedals.
Looking forward to learning what you come up with for AC for your cab.