If I did it often I may have spent money on a sight pusher. I'm a machinist and have a very good vise my Dad gave me, he was a tool maker. I used a piece of Delrin and a hammer. I didn't use a heighth gage, I just eyeballed in the rear sight. I bought a wrench for the front sight and lock tighted that with blue Loctite. I placed a scale on the side of the front to align with the slide before tightening it completely. If I wanted to get critical I could still move the rear sight but I'd say it's close enough as it is. Trijicons are advertised to be shock resistant, but still I wouldn't go crazy with a hard press fit, I filed a side of the sight a bit.
Over the last few months I called a couple of gunshops, one wanted $50 to do it, one was $25, the last one I called I got to talk to the gunsmith, he wanted $20. I asked him if he used a sight pusher and he said No, that he used a vise and an aluminum punch. After talking to him I decided to do it myself.