Magnum Heads

The rocker studs are 7/16", looks like plenty of meat on the pads.
You sure the lower threads are 7/16"? looks like 3/8" from here. There are studs 7/16"-3/8" BBC that work well in this combo. I've done that conversion for 20 yrs. God the PR pinch looks like crap.lol I have a set in the shop now that look the same,but not when they leave. Looks fine go have some fun.