340 cam for 318

In my first thread, I’ve decided to just square the deck and get it to 9.58 height.

This 318 will be 8:1 SCR

But in that thread talk of a 340 cam on a 318.

Doing some Google says the earlier 340’s were 10.5:1 SCR. Later ‘70’s were 8.5:1.

I also noticed much different cam specs on both.

I’d assume, but want to verify, used the ‘73? cam with my SCR?
Thanks,
Mike