[29od1]

Here's a pic of the passenger side mirror (albeit a very poor one) that shows the little lip area that you need to radius. You only want to grind on the stainless lip part that the mirror attaches to, not the ball itself. I think the ball is chrome plated and it would start to rust if the plating is ground off.

It took a couple of trial fits and grinding, the mirror now can turn toward the cab enough so that I can see out of it directly behind the truck. I'm not sure if the original mirrors were this way, the ones I have are repops. Hope it helps.