Nice one Keith,
I only have one frame, it's the same vintage as yours leapin. I have a couple of barrels from the same era as my frame, I have 2 custom barrels - one with split lugs and one with a solid lug, and I have multiple current production barrels (carbine and handgun) with split lugs. All my barrels fit my frame with no problems what so ever. Several of my barrels were bought here on GBO, and they too, all mate up, lock up, fire, and unlock just fine on my pre-easy open frame. I have not had to do anything to my frame or my barrels, nor have I even had to polish or replace any locking lugs.
I guess I just got lucky??
leapin,
Try any "new" barrel on your frame when you get it. You may be surprised to find that it works fine, which was the original intent of the Contender system to begin with. Sometimes it really does work out that way...