This is my advice: Using old components from a frame is never a good idea if you plan to build a complete frame; it's just not worth it.
I chose to use this company for my bottom brackets and have used them for my head tubes also. The parts are top notch and the customer service is the best. Now for the drop outs just buy some 3/16 plate and cut your own, it's not that hard.
http://www.cycle-frames.com/bicycle-frame-tubing/BOTTOM-BRACKETS/
I have used a few different sizes of tubing: I started with .065 and just finished a frame with .120 which seems to be the way to go. Another option is right between both and that would be .090 which is still good.
Your motor choice should determine your tubing thickness, china girl .065 or .090, big clone then go with .120
Hope this helps you out. You can also check out some of my builds to see how and what I have used and completed.