My 1985 Nissan 300zx None Turbo won't start.

first of all, if you knew it was going to sit for 5 months, I would have unplugged the battery ( even though you say it cranks) then I would have drained my gas out and found a way to secure it properly instead of letting it sit in the tank for so long. Gas it like milk, in contains different ingredients that will separate at some point. and milk is NASTY!! I would have drained BUT don't just burn it off and burn out your gas pump. How exactly did you check the plugs?? Did you physically unplug the wire and get a deep socket and pull out to see if it was getting spark?? Me, personally, if you say you get crank but no start, I'd go straight to the coil before the starter, but that's me. good luck