have any of you guys ever ?

Double up the main leaf, gouge out what you need, chamfer and polish. Yeah it will ride like a truck. but it will spin the streetskins forever.
Ok so not the best idea, but I agree with Blu, and others.
Spacers are cheap.
But I tell you one thing, If you've got just a cigarette-paper clearance there, it's probably a few papers short when the tire goes flat.....So measure with cereal-box paper;that should be plenty, so long as the short springs don't shift.
I broke both front springs on a gravel truck once. Here's a tip; if you find yourself semi-reclined,staring at sky, and still climbing,you probably forgot to open the tailgate, and when you finally realize this, clutching it is gonna normalize things rather violently.
Here's another tip; If you put your ditchdigger 18 year old cityboy into a gravel truck, just because he says yes when you ask him if he knows how to drive a stick, you might wanna rethink that.lol