Cut out the donor BB and got to work with large rubber mallet and a squirt of Kroil.
The donor seat tube needs to fit inside the ALiEN's seat tube. I drove a good 7 or 8 inches of tube into the other. I left the donors BB intact for the operation. There's just a bit of flatness now but new cups, bearings and crank should correct it. The donor BB does still spin freely so it really is just a bit from me driving it together with the mallet.
Chain line on these is always tricky. But I got the bottom half to go in a straight line. The top half is going to need a idler.
GC.