1990 allegro motor home; 454 GMC . We don't know how to change the belts and also wonder if there is a diagram we could look up. Are the belts all the same size, as in, if the 454 were in a truck or motor home? This home has been setting for quite some time, maybe a year; we're trying to get it in shape to be used again. Not even sure I'm doing the right thing by posting this. New to the site and saw some questions, but didn't see one like mine. If I'm not supposed to be on this forum, could someone kindly re-direct me? Thanks so much.