New boots gave plenty of spring clearance, but the holes in the lower mount had to be drilled off center, and regardless there is still a round section you're trying to bolt to. If you machine up some special spacers that match the curve and square it off inside and out it's safe, but the usual "stack of washers" I've seen isn't a safe option. Cutting new mounts is safer, allows for more spring options (thicker wires), easier spring changes and is the 'right' way to do things
-----
Okay, I'm bagged after a full day of work in the garage. Engine is rebuilt and ready to go in. This included the helicoil, swapping out two main studs, blue-printing the dry-sump pump and all the usual engine build items (endplay, checking deckheight, etc. etc.). New shock mounts are now sitting in wet paint...so things are looking up again. Can't wait to find out what the next disaster is! hahaha.
-Dave