As a new frame builder, with no formal training, I've learned some lessons the hard way. I'm just finishing frame #7 and went to thread the BB cups in and realized the BB was backwards. What is really mind blowing is that up to this point I've never considered which way the BB should go...just put it in the jig and built the frame. I can't believe I just got lucky on the first 6 frames, but somehow they all ended up with BB in the right direction.
OK, what should I do? Just reverse the side on the BB cups and tread in the reverse direction? Try to reverse tap the threads (seams like a dumb idea)?