what Baron said, good for you having a go at your own car and not just paying someone else to do it for you,which any tool can do, i'd say after doing what Baron said and if there is a problem in the engine it would most likely be in the bottom end probley rings which i believe you said the machine shop did, so no fault of yours.
the engine in my R32 was built by completely by myself in my garden shed ( new rings bearings and head gasket, making 1 engine from 2 broken ones) and i have had no training at all and it has ran a hand full of low 11s and been in car for over a year, so whats wrong with DIY and slapping it together
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