Find a 45 amp capacity generator and regulator for a Cadillac or an Olds 98, and don't bother with a second battery. Unless you're planning to run the air compressor with the engine stopped, there's no point whatsoever in using the deep cycle battery. The only real difference in a deep cycle is the fact it can be repeatedly discharged 75% instead of 25% like a normal battery without damage to the plates. That's important for a trolling motor or a golf cart, but not a vehicle battery.

Use a good-sized reserve tank, like a 30-lb. Freon tank with a one-way check valve, to give the compressor a little break.

Trailing arms and air bags will be a HUGE mistake, BTW. Add more leaves to the regular springs.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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