2006 Solstice (says hello). The engine overheated for some reason, going from ~200F to ~300F in a matter of seconds. (Actually, the gauge changed directly from 203F to 298F.) The head is over at the machine shop getting milled and a valve job. They said it was "pretty warped," but didn't say how much and it didn't occur to me to ask.
Now, obviously I need to check the block, as well, and I don't really want to pull the engine if it's not necessary.
This is a 2010 GM LE5 (Ecotec 2.4L) from a Malibu, aluminum block and head.
When checking with the straight edge and feeler gauge, how much variance is acceptable?