Try using the United machine on line calculator and or the Wallace on line
Using the same numbers will result in slightly different results on both sites
Make sure and try using the - and+ sign on the piston deck heights and piston dome volume, you should get less compression with the dish than with the same amount of dome volume. Which ever sign gives you the less compression using the dish volume will be accurate, if using the + sign on the disc volume gives you 10.5 to 1 and the - sign gives you 13.5 to one then you know which sign to use on THAT sight
Both will get you in the ball park though
Have fun and learn