Convert it to PT, replace the slugs with Warn premium hubs and don't look back.
IMO - I really don't see a reason to convert it and leave it slugs for a typical truck. Slugs are much stronger - but you are running 1/2 ton gear I assume.
I always locked the hubs if I thought I was going to go out and needed 4WD or when I was in snow country. In the winter I kept the hubs locked. Daily driving - left them unlocked.
Some guys running D60's will leave the slugs rather than taking a chance of blowing a locking hub.