Sorry, still not clear to me how best to help. :)
If your engine compartment is like mine, the placement of the motor (and the engine tin) in the engine bay is alone insufficient to isolate the upper engine from the lower engine.... and so my engine compartment includes three, removable, horizontally oriented, rigid-fiberglass panels that attach to both the car subframe, and the engine tin.... effectively separating the upper and lower portions of the engine from one another. As the panels bolt directly to the engine tin there is little need for additional rubber gasketing.
These panels are currently removed for my engine swap, I would be happy to trace them and mail you templates... the panels could then easily be replicated from the material of your choosing.
If this helps to solve your problem, please let me know and I will proceed.