shouldnt blow a head gasket.
look for fuel pump fuse under the dash if im correct.
should be k series also if im correct.

what i do, leave it or take it. i just unplug all the wires for the spark plug, so it wont get sparks. take the plugs out one by one after each test and put it back after that cylinder's test. if all the compression numbers are the same than its good. couple number off would be fine but if there is a large dip, 150/150/80/150, than you got a problem.