Compression Issue (thin head gaskets??)

yea were gonna mill the heads... the shop was supposed to give us an idea on comp but never did... so i cc'd everything and it was bad lol...

so looks like .080 off the heads... can you do that on these?? also i know they need to have the intake milled

How large were the chambers?

.0053 per 1cc with a 318 open chamber head

ive milled .045 and a friend milled .060 no issue.