The GM Chassis should serve you well. The 454 is a powerful engine. I have the TBI (7.4)454 with a turbo 400 transmission (1990 P-30). I have no complaints. I would suggest that you pick up a spare set of plug wires, rotor button and cap. Those occasionally fail to one degree or another. It's an easy fix but, only if you have the parts. I just keep the spares on board so, when I need them I'll have them. In a lot of the older P30 chassis the right front brake line needs to be replaced. Mine was replaced by a previous owner. Apparently they fail on the inside and cause that front right caliper to fail to release. It's an easy and cheap fix. Keep an eye on that master cylinder which is located under the driver's seat area. You'll see it when you open the dog house engine cover. If you need to replace the master cylinder it's an easy job and cheap. I replaced mine two years ago with a rebuilt unit from Advance Auto parts. After the core exchange it cost me like, $17.00 bucks for the part.
Someone else mentioned it and I'll say it again. Check your tires for age. Don't risk driving on old tires. It's not worth it. My OEM tires were D rated 16-7.50 or something like that. I replaced them (after a bad blowout) with 16-215s. I don't remember the exact specs but they are 215s and "E" rated, American made Coopers, made in Arkansas. They ride real nice.
I flush my radiator every two years and my old 454 runs nice and cool. Unless you know the status of your radiator I would suggest that you consider a real good flush. I did a lot of reading and chose regular old radiator flush solution from Auto Zone and I filled and flushed three times. It's an easy job that makes that big engine run nice and cool.
Change out your fuel filter. It's cheap. Heck, they sell the filter at Walmart (Fram). It's a little filter considering the amount of fuel it handles. Mine is located on the inside of the frame rail, right side, about halfway back, behind the steps. Changing the filter will make life easier on your fuel pump.
Check your roof over real good. If it's a rubber roof, and hasn't been recovered it almost certainly needs attention. If it's a metal roof they are super easy to work on. The EPDM rubber is too but, make sure to use only EPDM rubber compatible sealants, etc.. They sell that stuff at camping World.
The front end on the older P-30s have a bunch of lube points. I lube mine every few thousand miles. It's easy but messy. Check for zerk fittings on the drive shaft too (at the universal joints).
Take a drive to the coast and have a great time. We camp at the coast a lot. I love it. We never want to come home. We probably spend six weeks, or more, at the beach every year.
