Your choices for under chassis headers for an early "A" are Doug's (have a set and like them ) or TTi's (also have a set but haven't run them yet ). Each set has their good and bad points; they are both expensive, they each will take just about a day to install, Doug's are an erector set, you assemble them in the car, TTi's require you to trim bits and pieces off engine and tranny, TTi's have larger tubes, require special starter.
So word of advice is to contact each company get all the info you can from THEM, think about what you want to do.
Good luck!
