I've never replaced sights before. This will likely be a learning curve.
First, I bought 4 of these Mepro Tritium front sights which claim to be compatible with Armscor Rock Island TAC 1911 .45ACP. Figured I'd try them on the three 45 Standards I bought.

I then ordered 2 sets of Truglo Tritium sight sets for 5" government 9mm 1911s. I'll try them on a couple and see how close they are before ordering more.

Then of course, I had to order a new sight pusher because, well, mine got toasty…

I'll try the front sights first. If those work out, I'll move on to the sets for the 9mm.
First, I bought 4 of these Mepro Tritium front sights which claim to be compatible with Armscor Rock Island TAC 1911 .45ACP. Figured I'd try them on the three 45 Standards I bought.

I then ordered 2 sets of Truglo Tritium sight sets for 5" government 9mm 1911s. I'll try them on a couple and see how close they are before ordering more.

Then of course, I had to order a new sight pusher because, well, mine got toasty…

I'll try the front sights first. If those work out, I'll move on to the sets for the 9mm.