Hi folks. New to the forum and to the RV world. Just bought a "93 Pace Arrow with a chevy 454 which runs terribly. Backfiring, missing, no power on hills etc. I have read on various forums about this engine having this problem and ready to proceed with putting all new parts in the ignition system but I am stumped with one big problem. The size of the opening in the engine access door is just too small to get my arms in to reach the spark plugs. Is there a trick to it that I don't see? I looked from underneath and that doesn't seem viable either. Can someone help me with this embarrassingly simple problem?