My 355 LT1 was built up with TRW forged, dished pistons; dish volume 21.1cc, 4.030 bore, compression distance 1.560. Can anyone help me determine the effective compression ratio with stock heads? My guesstimate is about 8.5-9:1..... opinions please

Side note: My girlfriend would really like me to finish this project and get all of my car parts off the driveway and (preferably) in the damn car. Maybe even before it snows..... but maybe not