You need to study the several sticky posts concerning your problem - on the main Engines; Northstar threads page. Diagnose the apparent cooling problem(s) before hanging your hat on the head gasket(s) thing. Learn about "purge line".
BUT, it sounds like you bought a big problem. If you need to install studs the job is, for all practical purposes, impossible with the engine in the car. Too much interference, machining, block sealing (masking from aluminum chips), access problems. You will not need to resurface anything, and DO NOT use any form of ScotchBrite within 300 feet of the engine. Just clean the surfaces well with gasket remover and lacquer thinner. You'll NEED a real GM service manual set - either eBay, www.helminc.com or www.alldatadiy.com - just too many special procedures and reassembly tricks to wing it - for instance: Torque the crank pulley bolt wrong and you have no oil pressure.
Study the stickys as well as Tech Tips. You can DIY with mechanical expertise, lots of time and tools, lifts and a decent shop. A local Mom&Pop shop could do the stud job with a www.northstarperformance.com stud kit in about 4 days - lots of labor - and about $2500 +/-. You can also insert the block. www.huhnsolutions.com.
BUT, it sounds like you bought a big problem. If you need to install studs the job is, for all practical purposes, impossible with the engine in the car. Too much interference, machining, block sealing (masking from aluminum chips), access problems. You will not need to resurface anything, and DO NOT use any form of ScotchBrite within 300 feet of the engine. Just clean the surfaces well with gasket remover and lacquer thinner. You'll NEED a real GM service manual set - either eBay, www.helminc.com or www.alldatadiy.com - just too many special procedures and reassembly tricks to wing it - for instance: Torque the crank pulley bolt wrong and you have no oil pressure.
Study the stickys as well as Tech Tips. You can DIY with mechanical expertise, lots of time and tools, lifts and a decent shop. A local Mom&Pop shop could do the stud job with a www.northstarperformance.com stud kit in about 4 days - lots of labor - and about $2500 +/-. You can also insert the block. www.huhnsolutions.com.