No, those are the head bolts. As for which is better carb or EFI... that depends on a lot of factors, but generally EFI. But the EFI head is prone to cracking at the #5 exhaust valve iirc due to the smog pump blowing cold air at a hot, thin casting. The new Promaxx heads reportedly resolve this issue with a thicker casting. Yours may already be cracked so you'll want to get it checked unless you know that the bad cylinder wasn't related and it didn't have issues before... even so, not a bad idea to check. But personally, I'd keep the 91 as EFI if everything else about the truck makes it worth doing the work.
If you just want something that works, replace the head gasket and swap the motor. Donezo. You'll have to figure out the throttle linkage, bypass the fuel pump, and your cat may become clogged quickly, and of course you'll probably get worse gas mileage, but if it's what you need to get running, so be it.
But, if you're planning to sell the 86, why not just sell it with a running motor in it and use the extra money to get a reman motor for the 96?
As for the head gasket, Felpro 1024.