That's exactly what I did with my 91/30, is convert it to the PU scope. My scope is a repro- i figure if it's not authentic, i'll go with the looks and integrate new stuff like the fully moving FOV (it's pretty convincing, not one of the newer cheap ones) as well as the mount, i'm assuming.
To install it is super easy. The scope mount I got came with the appropriate drill bit to mount the screws and the retaining pins. I did mine on a drill press no problem, but if I had to do it again I would definitely have used a mill (if I had one accessible). Nonetheless, the drill press works- the mount base itself almost "snaps" into place under the interrupter- like it has nowhere else to go but be totally level
. I scribed the holes, got drilling, then tapped the screw holes. I had to notch one of the screws to allow the little setscrew to go in, but it looks fine. I did a pretty shoddy job of cutting the stock out, but I think it came out OK in the end. I would highly recommend using a jigsaw to make it nice and pretty. I think i'm just being too critical of it, it's probably better done than most of the originals
I can take a few pictures of mine at key points that you would wish to look at. I'm really happy with it, and all my friends love it as well
Also- I bought the bent bolt body from buymilsurp.com. I bought one off Gunbroker from some guy, and he did a really crappy job of installing the handle. The one on buymilsurp was kind of expensive, but the guy that did it really knows how to weld and polish, it's one of the best you can get. If you don't know already, that's also super easy to change and shouldn't affect headspace.