Engine questions on 96 evinrude 70 seahorse

Brothers, I just bought a little Boston whaler 17 foot Mantauk to play around with and for my kids to learn about boating and fishing on. It came with a 70 Evinrude Johnson Seahorse that has sat for several years. Surprisingly it cranked and ran ok and was able to take it out on a water test but it had no top end and began gurgling which I took it to be to be fuel problems. So replaced the plugs filter fuel lines and tank and cleaned the carbs etc and worked in it for half a day. Replace the tank and the lines because the fuel pressure was was not sufficient to fill the fuel filter more than halfway which we thought maybe a bulb tank issue as they were very old and now it won't crank at all. Lol. I can crank it with starter fluid but it will not run long. i suspect it is either the carburetors need to be rebuilt, power-pack is bad, or the Most likely i suspect the fuel pump may just be going out and too weak to keep the engine running properly. Any thoughts from the ob? Am I missing anything ?