Ok, I've got the whole "bottom loading" thing down, but my problem started with the spring that keeps the base plate in place. I tried bending it up to allow for a simple slipping in of the new follower/spring assembly and it popped a rivet on the front edge of the magazine. Maybe this is unique to 20 rd Colt mags, but I'm assuming that the spring (not the follower spring, the base/body spring) is presant on all mags. Its also on a universal I own and I'm having the same problem with that one.
Oh yeah, its also worth noting that these 20 round mags had 5 round limiters in them, will that pose any legal problems for me? There was a brass limiter arrangement which easily popped out.
So where do I go from here? If noone knows what I'm talking about, let me know so I can take a dig pic in the morning.
Thanks for the response Bee man!