Not exactly, but my 1st post I mentioned an inch narrower than what you were looking for. If I remember right about 65" from wheel surface to wheel surface.
Also some 3/4 2wd are 6 lug non floating but have some really huge drum brakes.
I don't see the point adding disc brakes, seems alot of people think drums brakes are junk, they are more than capable of stopping a vehicle. I prefer the feel of rear drum brakes myself.