Hot Rod Lincoln ? .....no...Buick!

Don't laugh, I'm collecting parts to build a nostalgia 1950's Hot Rod. It will be a Buick Straight Eight (320) powered Model A Coupe. My current search is for a manual shift belhousing and flywheel for thr 320 engine. I understand they are different from the smaller engine. What year was the last 320 (Roadmaster) available with manual transmission? Any leads? Incidentally, it will be a new rectangular tube frame, 18 inches longer than original. It will be full fendered. thanks, Jim