[Schurkey]

I put drain plugs into stamped-steel trans pans on my own vehicles. It's not hard, and it doesn't cost much. I've used "drain plug kits", I've welded/brazed nuts inside the pan, and I've used generic bulkhead fittings and a hardware-store nylon gasket. I don't do any of that any more.

Eventually, I figured out that I can pop a cooler tube off at the radiator cooler, drain the pan by pumping it out the cooler tube with the engine running. Costs nothing, extremely easy to do. When I refill the pan, I can pump new fluid through the converter, flushing all the old fluid out that same cooler tube. Depending on the size of the torque converter, 10- 15 quarts of fluid flushes and fills the transmission except for the servos, accumulators, and whatever is trapped in the valve body and clutch drums. (about a quart or so, maybe less.)

I don't see a point to a drain plug any more. And a drain plug that you don't install, absolutely cannot leak or drag on on an obstruction.