I was just interested in hearing your story as I also have mine to share.
I have an 87 TR. Plan on replacing diff. with Neuman unit, release bearing, clutch slave seals, CV boots, brake hoses, suspension bushings, etc. in next two weeks. Will take photos.
If you plan on replacing the 12 ring gear bolts they were NLA when I did mine. According to Paul(Newman) they also fail. I bought the last 9 latest style I could find and installed 3 12.9 grade socket head in the other holes. I still have a full box of them if you need.
ring gear = crown? those screws ( why you say bolt to them ) I always renew when I put them out of any reason. never use them twice - but only for being on the safe side. it would be too much work later if they would break
I wish you all the luck ! Please document this (with lots of photo's) as it becomes very valuable information for us all here David !