I'm always keen to change the hardware on my Squier Tele, as the stock stuff isn't amazing (don't get me wrong, it's good, but little replacement's like these are better).
So yeah, I put these on simply by unscrewing the previous string guides, and screwing these ones in. Had to make sure the orientation was right so that the groves were parallel to the strings, but that wasn't difficult. Now, my Tele looks just that little bit nicer. As for the sound, maybe there is a small change, but I haven't noticed it.