440 vs 360 GO!

Im not sure what was in the van, the motor is already pulled and the van is gone. I do have power brakes so I assume you are talking about the booster not clearing. Can I just pull the booster and go to manual brakes to create the clearance (the brakes are really touchy anyway). What kind of clearance is there for headers? I have headmans with my 360 now, and I just installed adjustable strut rods, boxed lowers, pst quick steer, 1.03 torsion bars and a big front swaybar so I dont think I want to change that stuff over for now.