thinking out aloud Searbs,
wouldn't mind a conical rear for my ossa dirt track project,i guess most later model's ran those f/rear,mine are just full width earlier (heavier) types,fronts ok,it's small trials type,if your'e going to use rattle can,use VHT engine/tranny paint(heatproof),it's if you can post cure it ,black garbage bag in the sun
,should become reasonably fuel proof,good luck with it,mick