I just did about the biggest bone head thing in my life!

Well after I got over the initial shock of what a dumb *** thing I did, I evaluated the situation. Lucky I drilled right over the rear drum so yeah I used a 1/4" Pipe tape and drilled the hole out to 21/64, tapped the hole and put a 1/4"brass pipe plug in it. I used grease on the drill bit and tap to capture the shavings. Since the trans is still empty, I'll drop the pan tomorrow and see if I can get some of the original shavings out.