Help! Swapped 302 heads on my 318.

Rockers off, ruler across valve tips/retainers
Well now lets think here for a sec, i gotta ask you stuff i always assume is done and therefore miss the diagnosis.
I base the 1st response on you saying it only sucked air at the plug and didnt push your finger off..that would mean the valves are open .

Btw Did you needlessly pull the distributor out when changing the heads?

I did. I also got it back to top dead center and checked the timing. Everything is good there.