Moroso "Permalign" transmission pan gasket ???

There are some steel core, rubber coated trans pan gaskets that Mopar sells. But you can find the same ones from the aftermarket manufacturer. It has raised ribs to concentrate the sealing loads. Should be available from Mopar, Summit and Rock Auto. I have some for a 904 but they certainly must have them for 727's as well. I'm at work and can't look the numbers up at the moment.

Slightly longer bolts can help reduce the chance of stripping out the aluminum threads. But the OEM length should be enough if everything else is OK.