Difference with two banjo rear spider gear housing/ring gear bolts

[Tim Ayers]

I'm in the process of getting ready to build up another rear end. I had a '40 rear that I was hoping to take the axles from. Turns out the gears are pitted by sitting in gunky grease.

When comparing two different center sections that I have, one of them has the bolts with safety wire holes drilled into them and castle nuts.

The other carrier does not have safety wire holes drilled and is topped with those "self locking" nuts. Both bolts are correct with the D shaped head

I'd think the safety wire set would be preferred in something like a rear end. If so, I'll swap them over to the carrier I'm planning to use for this conversion.

Thoughts?