If I were you I would buy a used Rigmaster unit without using the AC/Heat plumbing. That's a ton of extra hardware. Just the engine with the generator and alternator.
This setup will run you AC without breathing hard. Along with the following benefits.
.2 gallons per hour. Check what your planning on using. I think it uses much more!
Twin cylinder diesel using the trucks fuel tanks
Automatic start/stop when batteries need charging
6,000 watts to run other stuff when needed
You can call www.BigRigTruck.net. They have 2 locations. One in NE and one in TX. They probably have what you need used already. Have them install it. Have them wire it as one 50amp circuit instead of two 25 amp.
You can also find one on Ebay pretty cheap. Have it shipped to BigRigTruck and have them fix it up then install.
This is a worry free setup. Never have to think. In your case, it's a plus. Also get an Espar for heat and KEEP IT MAINTAINED unlike many people!!!!!