Cutting the tops off is not legal. If the piston has a higher than stock squish band, and you matched it to the stock piston, you may be considered legal , by the result, not by the method.
Any head will hit the piston, cut or not cut. I said to use an uncut head to get near the legal compression limit, not to miss the pistons.
You need to measure the piston to head space by deduction. You can use the clay method or the washer method. Take a 030 thic washer, or a valve spring shim washer( Iuse a 5/16 grade 8 washer). Place on the piston squish zone. Set the head and gasket on, and bolt it on at 25# torque. Rotate the engine, without the cam in, and feel for any touch at TDC. Do both ends of the engine, one at a time. Take the head back off and look for hard marks from the washer. I use permanant marker on the head and piston to show interferance.
You can also measure the piston protrusion with a pair of the 030 washers and a straight edge. This is quick and easy and works at the 030 gap size, if you run less space(under 020), the actual space should be measured, IMHO.
Measure the head gasket. It will be about 070( @ 25#) for the Felpro. Remember that the HG wil be about 066 at full torque value.
You will need to cut the piston tops off to get any room. I suspect that the engine will not be legal.
I assume that you would want to be as legal as you could be within the spirit of the rules. The head saver gasket and the stock size head may be close to legal compression and you would make any cc test if you were to go fast enough to get taken apart. In reality ,the SCCA seldom takes any cars apart. My circle burner gets taken apart every time we run it.
As you get more races and start to go fast, find a good block and builder(me) and go fast legally. HTH, Mike Ogren/Protech