"The whole arm is under $10 more than the BJ, so how tough is it to R&R an upper BJ?"
I always replace the UCA on these trucks I do not think you can press the ball joints out of the arm unless you get an aftermarket arm designed to have the BJ removed.
When I replace BJ on a gen II I buy two lowers and two upper UCA. I prefer the two piece pass side because it makes life so much easier but I am not afraid to convert to the one piece on the pass side either, just have to install shims.
Not sure XRF is available for our trucks? The XRF joint appears to have the stud completely encapsulated in the plastic "bearing" no metal..... I have not had good luck with BJ of this design in my experience
All good thinking, and I've done that four times on my trucks, four new CA's in one step. My question was how hard is it to replace the upper BJ, on my Moog UCA? The boots are all toast, the lowers might be Ford arms, that was ten years ago I'm sure, but given the care and low usage, I think those are Moog also.
I do the arms to replace the bushings, which are very dangerous to do yourself with a typical press.
Do you think the two piece arm is needed to get more camber? I've only done the one piece arms, since my first was my lowered Mountaineer with wider tires. I needed the clearance there where the two piece assembly connects. My last three have not allowed the height to be lowered any good amount, the camber they said were two much negative, though I prefer more negative than most people. My tires wear best at the limit alignment spec, not zero or positive camber. My Mountaineer was zero trouble, it could go much lower than stock, I think I've had it in the 3" lower than stock range since 2007 or so. I've used the same camber bolts on all of them.
I think my last three trucks have been barely under stock height, maybe 9.5" to the LCA bolt centers. This last white Limited was 10.25" on the right side, and 10.625" on the left side, as I got it, before the work. I replaced the arms Monday, and cranked the bolts out a lot, more on the left. The alignment shop worked on it, and then asked me if where he had it would work. He had adjusted the right side as low as it would take the alignment, and the left side was a little lower. I went with that, I think I measured 9.5" or just under when I got home, my driveway is not really level left to right at the spot I parked on, it could be off left to right 1/4" I think.
What shim is that you mentioned, is it a gasket that goes in with the hub, with the lower half cut out? I saw a reference to a shim on Amazon that seemed to match shape, but had no application or instructions. If that's how that works, what is the gasket made of, and how much camber is it worth?