or before doing a compression check as that requires turning engine over so could do more damage if its been starved of oil

take your dizzy out and put a drill on the allen key bit, this will spin the oil pump to see if your getting oil in the top of the head, so just take your turbo oil feed off and see if any oil comes out

also if you turn your igntion om see if you have an oil light, as when you spin the oil pump with a drill the light should go out, this a is a sign that you are getting oil pressure above 7psi