Originally Posted by Dfish1247
Forgot to add, i forgot to ask which thickness head gasket to use, so that’ll be ordered when I get the motor
You will need a thick stainless steel rule, minimum 6" length, and a good set of feeler gauges. I use a magnetic base and dial indicator to find absolute top dead center of each piston, but if you take your time and experiment with the rule and feeler gauges, you can get the piston dead nuts at TDC. I like to have the flywheel/flexplate bolted onto the crank and use a 24" long heavy-duty screwdriver that I call Dirty Harry to engage in the teeth of the plate and wedge against the bolts that hold the motor to the stand, in order to turn the crank slowly as I check and re-check for TDC. This prevents using the damper retaining bolt to turn the crank, which can loosen the bolt if you have the damper installed and have to back up the crank.
Stand your rule on edge and span the piston in line with the wrist pin to prevent rocking the piston on the pin and getting an erroneous reading. Use a felt tip permanent marker to write your finding on the piston crown so that you can choose a gasket that will give you the clearance you want on the tightest piston. It is possible that you will find a variance of around 0.005" from the front to the back of the block. I hope the range of clearance is smaller than that, but all you can hope for is that they will all fall into a range that will allow you to choose a composition head gasket that will put your squish/quench somewhere between 0.035" and 0.045".
Doing this procedure according to the firing order will shorten the time required. Firing order is 1-8-4-3-6-5-7-2. So, if #3 is very close to TDC when you start, you would go 3-6-5-7-2-1-8-4 for instance. That way will require only 2 full turns of the crank.