The FWD/455 engine set up was used in 23' and 26' GMC motorhomes. They look alot like an airstream, except painted. The Toronado running gear would propel the motohome from 0-60mph in 22sec. Starting in '74 or '75 the engine size was reduced to a 403, adding an additional 4secs.
(o.k. so it is useless trivia
I used to be a big fan of those early Toronado's...till a had a look at a '66 Riviera sporting a Wildcat 465ci motor...the whole car in black, inside and out...man, I still get a googly eyed when I think about that car.