pinion angle question??

i hung a degree measurer off the bottom of the driveshaft-at the rear ujoint it measured 0 degrees then i sat it on top of where the snubber bolts.it also measured 0.am i doing this right.i bought 4 deg.wedges today to run.i was getting new centerbolts for my spring packs and the local machine shop/welder is going to add the wedge thinckenss to the pins so they will be securely in the pad of the axle.he said he would do it for $5.so i can't do it myself for that.according to my dads old blue mopar connections book(mopar bible he calls it)it says i need between 5 and 7 degrees down angle on the pinion w/the superstock springs.so i am hoping the 4 deg.shim will do the trick.thanks guys for all the info...keep it coming.i am starting on it this weekend when i can go to the farm next to work..