Clean the block w/ degreaser and a high power spray so you can see if you still have a new leak. Remove lifter covers, scrape old gaskets off. Inspect for defects: bends, rips, flats, tears, etc. Get fresh gaskets -- neoprene not cork -- Fel-Pro or eqivalent. Put fresh gaskets on w/RTV on the tin side. When RTV is dry, replace on block and tighten [3+3] bolts. Do not overtighten. Check for leaks.