As BMCM showed, unless you shorten the magazine tube you won't gain a lower profile with 4506 bases. I'm sure you understand.
Maybe another option would be using pre-rail 4513TSW bases. They won't make overall length shorter but the finger rest will be gone so that's something. I don't use them on 7rnd .45acp magazines but do on my CS40 and CS45, (with custom grips,) and of course my 6rnd 4513TSW.
They are difficult to source but can be found.
Jim