Just put on a set of BBK shorties. I took off a set of Blackjack semi longtubes from 1987, so I had to jack the engine anyway.
I had the smog tube removed, and the starter loose, the alt out of the way, etc.
The pass side was tight but went in. The drivers side was easier, but it is still very close to the steering column and u joint.
I shimmed it, and finally changed the left mount, raising the mount to frame bracket location a bit. This seems to clear for now. I think it will settle down, but I will deal with that.
Overall, the BBK's were a thousand times easier than the longtubes.
If it makes you feel any better, I pulled the motor on my 66 Chevelle this weekend, and even being a much bigger, brand C, traditional muscle car, it was at least as big a pita as the Capri! The header bolts are much harder to access, the plugs are worse, and the headers still won't come out with the engine in the way.