Here's my old one, obviously not factory original, but it has 5 (6?) wires at the plug, and I have no idea what that thing is at one of the attachment bolts with a hack red wire attached?

Here's the underside of the new Napa regulator, only has 4 tangs for the plug, again my old plug has 5(6?) wires not 4, I haven't unplugged it yet to see if it too is a 4 tang unit though despite the different amount of wires.

If the both turn out to be 4 tang units then I'll just hook up all wiring the exact same way and leave it as is for now, unless anyone knows what's going on with all that and has some advice? (Clearly this is not my field of expertise, just want to be sure is all)