Had same problem this year in my 02 xstar. Pulled motor that night dropped off at local machine shop, had them locate new block and build to manufacturers specs, picked up 2 weeks later and installed that night and everything seems just like it never happened. Talk about a sick feeling when your wife tells you the engine feels rough and you open motor compartment to find oil and water blowing out valve cover. In the end it was a $2200 adventure with me doing all the removal and install. Approx. 4 hours labor in and out.
1970 Nova SS