Re: WOW ! I thought I was on my own...
Yeah, I did drill my frame, because it's a thick steel beach cruiser, but it was an all-or-nothing deal, and I didn't really like it. (drill it wrong and your bike is trashed).
I didn't know at the time that there was a $10-20 bolt-on adapter for that. Someone here will probably give you the link. Don't drill it! Especially if it's aluminum.
1" roller Dax Friction Drive and Tanaka 3300 with mods.