I looked at my 63 today and the bell crank does look like it would be daunting to line up. The bell crank is mounted with ball pivots, and they can forgive some mis-alignment. If your careful I would think you could line up the pivot point on the frame by sight. You should be able to clamp it in place and move it around till it feels right. If one clamp doesn't hold it mighy take a deep throat to get the firewall side. The frame on the firewall side of the frame pivot appears to be notched for the bell crank lever to clear. Good luck.
LG
