[denisond3]

Well, there should be a plate between the bellhousing of the transmission and the matching surface to that on the engine. There isnt a separate one between the starter and its mounting surface though. Other than spacing I dont see that the piece of sheet metal has any purpose. It has no threaded holes in it, and all bolts for the engine to trans and the starter support just go through it.
So if your car is missing one, then the torque converter would be held about 3/32" closer to the transmission than it should be.
It should be visible if you look at the engine-to-transmission joint.
The plate has to go on before the flywheel does; since it wont fit over the flywheel. Likewaise, it cant be removed with the flywheel still on the crankshaft.