How to get MFC (using VS 2010) to let me draw my own title, menu, border?

Question

I have a legacy MFC app. I want to modify its look & feel by removing some standard Windows UI elements (caption (aka title) bar, resizable window borders) & replacing them with my own versions.

I tried adding:

cs.style &= ~WS_CAPTION;

to the existing CMainframe::PreCreateWindow() method, which is "supposed to" remove the caption, but it had no effect that I could see.