Door Hinge Bolt question

[roadsterdude1600]

About to reinstall my doors on my '70 restoration, but cannot tell if the holes are 6 mm X 1.0 or 1/4X24 SAE. I assumed 1/4, but 6 mm seems to fit better. I need to clean up the threads after paint, so before I pull out my tap and mess something up, thought I'd ask. Also after reading posts, I am going to order some allan head studs so that I can align the doors better. Sounds like a good trick. I have seen references to both sizes in the forum, so not sure what the '70 should be. This car is driving me crazy with some SAE and some metric, and there seems to be no rime or reason. I'm getting paranoid.

[JT68]

All year hinge bolts are 1/4-28.

The metric ones (later years) you are thinking of are for the latch receiver on the rear door pillar, not the hinges.

[FergO2k]

So here is a trick that I heard when walking around a recent car show. (similar to tool doweling)
Before paint, hang and adjust the door. Then drill a tight tolerance hole the size of a nail thru both hinge and door post.
Send it off to paint.
Now when returning, put the nail into the hole and you should be back in same hung/gapped location when tightening up the bolts.

[roadsterdude1600]

Fergus, great tip for my next restoration (I have 2 on the shelf). Well worth the price of admission to this forum! Thanks, and I am re-tapping (or just using a thread cleaner where I can) 1/4 X 24. Peace of mind.

[dynaguy]

BTW. thread is 1/4-28.

[roadsterdude1600]

Right - 28 my bad (fine)