If you look at a lot of the manifold or head removal stories here you will often see experience with broken studs, helicoils, tap dies, etc. (most of which I have learned about on this forum). It appears that you removed your head and manifold without breaking a stud...is that right? If so, congratulations.
I have been rebuilding my exhaust and will make final tests this spring. I mention this because I thought I might need to have my manifold off and I was planning to have it reconditioned if I did, spoke to a machine shop in Allston, MA that would do it well and affordably. Might be a good time to give the manifold and exhaust system some TLC.
All the best with your work, sailing, I sail out of Salem, MA maybe we will cross paths this season.
Here is a link to contact information for my machinist in Allston. (Out of your way, maybe he has referral?) He mostly works on race cars though does a lot of side work. His shop meets requirements I have seen posted here. (viz. hard to find entrance, shop owner communicates in single word answers, cash business, no answering machine or other communication assisting technology, etc....).
https://photos.app.goo.gl/tR2vGQEwWvNWxkqk7
Stay well.