I'm bumping this issue back into the light, to see if there is any consensus to what, exactly, a factory RSR engine mounting bar looked like. The last thread on this subject that I found here didn't have any real answers in it.

I've seen three types:

A standard 911 part with 6 holes drilled/punched into each half (only one stiffening flange).
As above, with an additional flange welded onto the bottom.
A part with both flanges cut as part of the original piece of metal and bent on a brake or press; plus the 6 holes on each side.

Were all three versions used on a factory car at one time or another? Do they predominately resemble only one of the three types above?

I have one of these and I'm trying to figure out if it's an original part, a reproduction from years ago, or something altogether different (911SC/RS, etc.) All I know is that it's not something that was made recently.

Thanks,
Jeff