I have the TPU rear sight on both of my 75B's. I installed them myself...the installation is easy once the old sight is removed, but in removal one of mine was easy and the other wasn't. I padded the slides with 1/8" leather and clamped them tightly, but not too tightly, in a 4" vise. The slides were set so the emerging sight just cleared the vise jaw. My 75B SS came out with moderate taps with a brass drift. I had to pound the snot out of the black 75B using an old steel nail set ground to a point to get that one out (I tried the brass drift, but it slipped and dinged the polycoat).
I do like these sights at lot, but they do interfere with cocking the hammer.
Kim