i need a new balancer for my 5.0 and figured that i would get a new sfi one.i looked at the professional products ones from latemodel resto.the same #balancer that i've seen on ebay from various places say you have to measure the height of the balancer and you may have to order a spacer.has anybody used these before or had any experience with them?i don't want to have to shim the pulleys,if it's too much trouble i may have to empty the wallet for a tci or ati balancer.late model says nothing about ordering shims or spacers.