The oil pan choice should be obvious with the Milodon road race pan. It has plenty of baffles to keep the pickup covered. I really don't think the cross-ram would work without major tuning and modifications. The Nascar deal would be the better choice if you can find one because they do pop up once in a while for sale.
There are still some old guys still alive that used race those old cars turning left and right so they might be able to give you some parts information

Gus