Believe it or not, but one French company did it right in the 80's. Mafac/Spidel, actually designed their pad holders for their sidepulls to be canted couple of degrees in relationship to their caliper arms to produce the required toe-in out of the box. They even beveled the edges of the brake blocks in their molds so you don't have to do any sort of grinding before you mount them on.
One of the reasons I love my LS2 Spidel sidepulls. It had been a plug-and-play on all of the ones I put on my bikes since the 80's.....no judders, no squeals right out of the box!