I'm not 1911 sophisticated enough to know if I'm correct in my purchase or not but there are a couple of reasons I ordered those heights. I love the Truglo night sights I previously purchased but their usage charts seem to be contradictory and ambiguous. They denote the barrel length and caliber as criteria for choosing the proper height of sights for 1911 pistols, but then offer night sights like Model TG231K which is offered for "Kimber® 1911 models with FIXED REAR SIGHT sights". Well, that would take in a variety of barrel lengths and several calibers of Kimber 1911's. I took a leap of faith a couple of years ago and purchased those Model TG231K's for my 3" Kimber, and they work great and are very accurate. I would like to believe Truglo did not design those night sights for 3" or commander .45 caliber Kimbers only. Ultimately, I'm going to try them on a Kimber 5" 10mm 1911 too.
My Remington Ultralight Commander is only truly accurate for me when I have the rear adjustable sight screwed all the way down, so I believe the lower rear sight height may work for me. Also, the TG231N1's (.260 Front / .450 Rear) I just purchased indicate they work for "Ruger® SR1911 Models with fixed rear sight" as well. Again, that would encompass a couple calibers and several barrel lengths from Ruger on their SR1911's, and as I previously posted, I have a Ruger Commander which I will put the sights on if they don't work out on the Remington.
Also, I believe I read a review on Ebay or Amazon that an individual installed the .260 Front / .450 Rear's on a Remington Enhanced Commander and they fit and worked well. I always get the Standard Truglo Tritium night sights from Ebay, and they are pretty cheap, so I can experiment a little bit. I'll let you know how it goes, but it will be a couple weeks in all likelihood. I hope you like your Ultralight. I love mine.