Exhaust studs. The factory stud length is 30mm and I’m planning to use aftermarket headers. There is some forum discussion about insufficient length with some headers but not enough detail for solid decision making.
Found “premium” studs left over from the e36 that are 42mm.
For solid data, the header source was consulted about this and learned the factory studs will be long enough but just barely.
That cemented the plan forward: use the longer studs to ensure safety margin. It took awhile to remove the old studs and the new will likely be as fun to install.
Filled more of the day with brake line research. BMWs use a bubble flare on their brake lines which I needed to know. The original hardlines did not survive and replacements are needed but new lines are not pre-bent. In case of error bending the lines, I may need to make different lengths and will require flaring the ends. This post at rtsauto.com was helpful.
It’s done. We’ve removed all of the metal (plus a little more) that we think can be removed without compromising the integrity of the chassis. Next, it will be blasted, primer applied, then sent off for the cage.
Hoping that more weight can be removed but leaving that decision and execution to an expert (cage builder).
Wrapped the last bits on the shell. Trimmed edges in the trunk – we removed it in a hurry and the jagged edges were a hazard waiting. Removed rust from the inner fender wells and trimmed the inner most sheet of metal then attacked the last bracket … it won but it’s not pretty.