On my 79 k-5, I have the original 12 bolt, with 4" TC springs all around, I got my new driveshaft and I need to tilt the pinion up. I ordered a 6* shim from TC and then called the guy back to cancel it. Well it came anyways, so now I have a set of 6* shims. After more research I had my heart set on putting some zero rates under there with a 6* milled into it. My question is does it sound unsafe to run zero rates and the shims together? Could I weld them together? and then pin it up? Just looking for other opinions. I got 4" lift springs so I wouldn't have blocks,and I don't want to get a chance of having more axle wrap.