I would take that 430$ and get a used engine with a 90 day warranty.

rolling the dice you have crapped out with mag heads,looking at worn heads,waiting on old heads.

I bring a JY engines home,strip and clean them,change all gaskets exept head gaskets,3 cans of plasticoat hemi orange and they look new.

300$ for a 91 318,I just swaped in my lunati roller cam/comp 901 spring with heads on engine.

picked up another 88 roller cam 318 for 300$ used with 90 day warranty.fixin to pop a roller whiplash in this one and let it rip rollin the dice for 800$

less time & $$$ in the long run with lots more fun wearing/breaking used junk along the way for me.

even the 440 in my sig pic was a 300$ engine I built the truck around,70,000 miles on the clock and runs great.

give you local JY a call while you wait and see what they have on the cheap.

I feel your pain with all that has gone wrong on your project latly.