I got the heads back from the machine shop the other day. No cracks & good guides so just a valve job and i had them install GMP Upgrade Valve Springs and Retainers. I believe people call them the GM Blue Springs because of their color $70.95 for the Set and the new Retainers $3.95 each or $63.20 for a set. According to GM and Some Local LST guys they work great and are priced right