I've bought a very nice, one-owner car with 103K miles that needs a valve body replaced to make it right. It's worth it, so I'm gonna see that it's done. How big of a task is it if I try doing it myself? Can it be done without pulling engine and tranny out the top and separating? All advice is appreciated. I'm not ASE certified or anything, but not a stranger to a wrench either. Thanks.