If you do all those in your bucket with a rat tail file like the one on the right you'll never get your 15 together. :-) Bin there, done that on
a few before I bought a 5 gallon bucket of old bolts. Square bottom ones are used on some of the early brass cars; round bottom later. I don't remember exactly when change took place. Nice modification job. How's the 15 coming?
Slow but steady. Yesterday I worked on some figure eight shackles and took apart a correct rear spring for blasting. Maybe I'll have the car ready to drive by spring. On the nuts I use a little grinder. Much less work than a file.