ALL gaskets should be installed dry, with very few exceptions....imho. The re-usable gaskets can be installed with fluid on them, and they will still not leak, so they don't have to be perfectly dry when changing fluid, tho it is better to be clean & dry.
I'm bettin your leak/seep is something other than the pan, Dave, unless your pan is messed up. 1/4" overfull won't hurt anything, but it certainly can cause the fluid to spew out of the vent when it gets hot. Trans fluid expands as it gets hot, which is why there is a "Cold" and "Hot" marking on the dipping stick. Hot fluid should be in the middle, between the cold and hot limits. A
little over is fine, as far as operating functions go.
My only suggestion is to use some brake cleaner, and spray the whole thing off...get it nice and clean. Drive it, let it sit overnight, and look for seepage/trails.
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Joel Adams
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