This was the front end of my BJ7 after the V8 swap. The distance to the center of the wheel arch is supposed to be 28" in stock configuration:
The fix was pretty simple. Buy eight Grade 8 bolts to replace the bolts holding the spring pans, but about 1.5 inches longer. Buy 24 matching Grade 8 nuts. Also get an all-thread rod of a slightly smaller diameter as the bolts and four matching nuts. The rod should be small enough that the original fixing nuts canpass through the rod without interference. Put the front of the car on jackstands and remove the front wheels. Place a trolley jack under one of the trunnions and remove two of the bolts securing the spring pan diagonally across from one another. Cut the all thread so you have a couple of lengths about 10" long and insert them in the holes where you removed the bolts and use nuts on the all thread to secure them in place. Now you can remove the remaining two bolts from the spring pan, leaving the all thread to secure the pan. Slowly release the trolley jack to let the front spring drop as far as possible. If you want to be as safe as possible you can pass a loop of chain through the coil spring to secure it in the compressed position. Now you can slowly release the nuts on the all thread until the spring pan drops out and you can remove the spring.
Reassemble but insert two of the Grade 8 nuts between the spring pan and the wishbone base. Wind up the nuts on the all thread until the spring is sufficiently compressed so you can insert the longer grade 8 bolts in the remaining two holes, making sure to install two nuts between the wishbone and the spring pan. Now just run up the nuts on the all thread and grade 8 bolts until you have enough clearance to remove the all thread and replace with the remaining grade 8 bolts. It's way more complicated to describe than it is to do. When you're all done, you'll have the spring pan secured by four grade 8 bolts with two nuts as spacers on each bolt between the spring pan and wishbone. This will drop the front end about an inch, like this: