The heads are off, swap them or not..

Yeah I've read that at least the 1970+ 318's gave 8.5:1 compression WITH flat tops, awesome :) plus the Sealed Power ones look just like this in pics.

Does anybody have an opinion on those 66-67 273 heads? I was going to have the existing ones milled in hopes of gaining around a half point of compression.

If the 273 heads will flow the same, but give a half point on their own....hey I'll mill those and get around a full point, so at the very least I should be running approx 9.5:1 which I can live with in this engine!

I just need to make an informed decision, given that these heads really don't NEED any work - whereas if I use the 273 heads they will need a rebuild for sure, adding a couple hundred bucks to the cost of this little side project, and I'm sure that these will not be super easy to unload for decent money, so I'm not counting on them to help me re-coup expenses building another set of heads.