TH400 leak

[70STOVEBOLT]

I know this has been beat to death. I have a cast aluminum pan and I have tried a rubber gasket and a Fel-Pro fiber gasket, to no avail. The transmission is a fresh rebuild that I did myself, replaced all bushings, seals, o-rings during the rebuild. It is NOT coming from the speedo gear housing, kickdown connector, shift shaft, modulator, dipstick or cooler lines, or pump or front seal, I have verified this. I have torqued the bolts to factory spec. Before the rebuild the stock pan leaked, the flange was pretty wavy, so I put a chrome pan on it with the Farpak gasket that the kit came with, and it leaked right away, so I put the aluminum pan on and used the rubber gasket that came with it. Leaked almost immediately. After the last gasket that I tried, which is the Fel-Pro, I have leaks and I haven't even filled it with fluid yet! I can see it running down from around the bolts, which are the socket head type and have a flat washer and a lock washer on each of them. Anyone with this same experience that has come up with a solution?