A way to save the sump, Ted, is to re-tap the problem hole and install a 7mm stud. You'll have to drill the drain plate, of course, it will now only go on 1 way and unless you can find a larger copper sealing washer a little bit of rtv silicone will be needed, but you'll only have to do it once because the drain plate has a center plug/bolt.
A guy I know used 7mm studs in the bottom of the case to make the case to sump connection stronger, as he uses a Berg sump and they are heavier. He drove the car to Central America and back last spring and has driven to Mexico 3 or 4 times over the years, all on a 78x90.5 (85 or 90,000 miles?) that I don't think has ever been apart.
I have also heard of guys putting longer 6mm studs in the bottom of the case and putting nuts on the inside so the studs (with a little loctite) won't be able to move.