I recently picked up an old trail boss for cheap, been trying to work the bugs out and get it going.

its been sitting for many years it seems, but it fires right up first pull if I give it more than half throttle, it will not idle no matter what I do, it feels extremely lean, has next to no power unless I rev the snot out of it.
things I've done:
- I've cleaned the carb extensively
-deleted the oil injection and run mixed gas
-replaced crank and water pump seals (crank bearings also have no play)
-changed the oil in the counterbalance
- put new Reed's in
- It has about 120 compression

I'm also about 90% sure the headgasket is blown, it pressurizes the rad instantly after firing, and it billows white smoke.

So, two probably unrelated issues:
-Blown head gasket
-possible vacuum leak

Redgarding the running issues, besides the crank seals, where could it be sucking air in? It is so lean it just immediately dies if I give it less than 25% throttle, I've cleaned the pilot and main jet, sometimes if I rev it it will run beautifully and pull hard, but not below something like 3k+rpm, also, there's oily residue leaking out around where the exhaust bolts to the head.
Carb boot is new as well