2020 small block race?

273 .060 for each Cubic in.
318 .05
340 .045
360 .0425
318 mag .049
360 mag .0416

Taking into account that a 408 would automatically get a -0.4 for the overbore and playing around with the above thousandths it didnt work out as a
408LA would be -2.04
408Mag -1.9968
Not sure if that would be a good indicator.

This is if just using the chart and some math. Hence the need for a cubic inch chart.