Getting the engine to line up with the transmission is the most stressful part of any swap. If you are working with a Ford EFI 5.0, for example, the long intake plenum and rear-mounted components make the tilt angle critical. A plate allows you to set a specific pitch and maintain it. Because the plate is bolted to multiple points on the intake flange, it acts as a rigid handle for the entire engine. You can push, pull, or tilt the block without worrying about the mounting hardware shifting or sliding along a chain link.