So I'm sure other have had problems with the seal around the opti spark drive on 95+ models. A couple of guys and I figured out the right dimensions to use to replace the stock style seal with a traditional spring type seal. We found that Napa part # 21098 fits perfectly. We replaced this seal on a few LT1's and then checked back at 1000 and 3000 miles. neither motor are showing any signs of leaking. We're still not sure on the longterm strength of the seal, but we are estimating it should go just as long as the stock seal.