I Messed Up - HO52 Pinion Pre-load

[USAF]

Wanted to change the fluid in the HO52 in my 72 K20 and what I thought was the fill plug was actually the pinion pre-load bolt. I did change the fluid and put the bolt back in at as close to the same depth but I'm sure that it's not exactly where it should be. What do I need to do now to make sure the differential won't get messed up? I did a Google search and there's a few mentions of pinion pre-load but not specifically for the HO52.

After I added fluid I see that the pinion seal is now leaking as the person that had it before should've changed it but they didn't. I was wondering why only about 1.5 quarts drained out and now I know that the proper amount must have leaked out the pinion seal. I'd like to change the seal but can't find any resource to show how to do that either. Maybe it's easy but I'm now apprehensive on doing anything on this differential.

I've only had this truck a short time and am trying to get all potential issues corrected but now it looks like I may have messed it up.

Thank you if someone can provide help.