Healthy Head?

Unfortunately I haven't quite been in the game long enough as y'all folks to truly understand the extent of what needs to line up for what I thought was just a "remove old and pop in new gasket" job.
Coming into this project as my first I was not expecting such fine grained requirements as I've been so informed - so please : pray_emoji : excuse my ignorance.
I'm just a guy that inherited a car that's been sitting for 30 years without turning over once. Got said car running. Said car developed a smoking problem - which turned out to be bigger than originally understood based on some online research and in-person talks with my mechanic friend.
And the rest is history...