O.K I have a few questions on what parts I can/should use for this project. I have a 90 b18a1 and a 94 b18b1, they have about the same milage. Which is the better? The head I have is a sir1 b16a. I also have the b16a block, and I have a 00 b16a2 block, can I use any of their internals?One last thing, the obd1 pr4 would be better to use then a pw0 or pr3 right?