Greetings, I have both success and a hiccup to report:
The XS Sights were delivered very quickly, but I held off getting them installed because Ripsnortr had mentioned in his Aimpro Heat Shield install thread that he thought the the heat shield might just slip on if you only had the bead sight installed.
The Aimpro heat shield was delivered on Saturday and feels to be the high quality that I expected.
My description of the installation with some pictures of the finished product, followed by the "hiccup" with my sight installation follows: (I'm sorry I don't have pictures of the heat shield installation process).
The heat shield installation was, essentially, as Ripsnortr described. However, I was not able to just slip it over the barrel with my bead sight as he surmised that you may be able to do. The bead sight was still just too high. You could probably bang/force it over, but I didn't want to damage the parkerized finish on the barrel or shield.
So, I just removed the barrel from the 590 and slid the wider, rear bracket over the end of the barrel until it slid snugly over the wider end of the barrel that goes into the receiver. At that point the front bracket of the heat shield was behind (or nearly behind) the barrel retaining ring (sorry if I'm using the wrong terminology).
The front bracket is more narrow than the barrel and you are going to need to snap this around the barrel to continue. Both surfaces being parkerized metal, they are rough and you don't want to scrape them across each other too much. I put a couple cotton squares between the barrel and bracket and was able to squeeze it together easily with my hands.
The kit comes with two different length bolts, a washer, a nut, and a plastic spacer for the front bracket. The instructions say to put the shield on the barrel, and tighten it down with the long bolt to compress the front bracket enough to use the short bolt. The front bracket on mine was already too wide for the longer bolt to get any purchase on the nut. So, before I re-installed the barrel I padded some vice grips with tape and squeezed the front bracket to make it a little tighter.
I used the long bolt, a socket, and allen wrench to compress the front bracket to approximately the width of the plastic spacer. It's important to just turn the bolt with the wrench and hold the nut steady to not damage the finish. Use the washer between the bolt and shield and just the nut on the other side (again so that you don't damage the finish with the spinning bolt). Remove the long bolt from the front bracket once you think you have compressed it enough.
I reinstalled the barrel on the gun. The pressure between the ridge on the receiver and the plastic spacer against the barrel retaining ring is what will keep the shield in place. Push the shield as far back as you can and slide the spacer in place. By applying pressure in both directions (rearward on the shield, forward on the spacer) I was able to get the holes on the spacer to line up with the bracket (the instructions do say that you may need to trim the bracket). Put the washer on the shorter bolt, put the bolt through the hole, and tighten the nut by turning the bolt. As it got really tight, my socket wouldn't hold the nut anymore so I padded a pair of needle nose vice grips with tape and really snugged it up.
A log narrative, I know, but all in all it was pretty straightforward.
OK, so the hiccup was with the XS sights. I didn't realize it, but the front sight requires a front, dovetail ramp that does not come in the kit. Once I get that, my gunsmith says that it will be about $50 to install. A grand total of approx $200 (plus the front ramp) to add ghost ring night sights was more than I was expecting, but I'll end up with the gun that I want and should be about done.
I've spent my time back home writing this post and haven't looked for a dove tail front ramp for the 590a1 yet. Anyone have some tips?
Best Regards
John