Will the gov lok interchange between the two? Not hardcore, but I need one for my '00 1/2 on DD/tow rig.

It should, but I certainly would not install a gov-lock in anything. They are ticking time bombs. Get a limited slip unit if you want traction without the harsh characteristics.

They are known to go bad with abuse and or large tires. I have a G80 in my '94 FS Blazer with 150K on it....no problems to date. Recently had the rear cover off for fluid change. All looked good. IMO on a DD or tow vehicle they do well. They can go boom like I said with abuse such as intentionally spinning on a loose surface then hitting a hard (high traction surface) or running larger tires/offroad usage (I would guess 33" and up would stress the unit too much in offroad situations). Are there better options, sure but they do OK for there intended purpose and usage.

EDIT: This will help, from a few pages back..... http://www.zr2usa.com/mboard/index.php?showtopic=14484