With that much in labor have the place doing the work get the engine. If there are any problems and the engine needs to come out they should not charge any additional labor.
Get a reman 5.7L.
Order or download the VP factory manuals. You may have to pay for some. Cannot always download them
Have you tried to jiggle the shift lever while still in N. Does it help? Interlock switch adjustment or defective.
I would send out the carb to be rebuilt by a professional. Many just throw on a carb rebuilt kit but don't get all the passages clean. The professional will use an ultrasonic cleaner.
But first check you choke.
Why go to a single wire alternator? They are mainly for hot rods. You need #4 gauge wire, possibly #2 gauge depending on how far away the battery is from the alternator.
The problem with a single wire alternator is they don't always properly sense the battery due to load.
I would guess...
Get a new heat exchanger at Lenco Coolers. Or MrCool. You could have internal damage in the heat exchanger. I would not bother with the old heat changer.
I just hope it's marine rated. Anything in the bilge like a relay or electric motor needs to be marine rated. Otherwise some gas fumes in the bilge and boom.
If your boat has a fuel pump it almost certainly has (or had when manufactured) a neutral safety switch. It would have to be really really old boat you with a mechanical fuel pump before the government required them.
Take a short piece of wire and go from the red battery cable going to the...
It looks like the yellow wires coming out of the shift control is the neutral safety switch. And the yellow going into the starter solenoid. If moving the shift control a tad forward and a tad back does not help then start at the yellow wire going to the ignition switch and move along to the...
Typically an alarm sounds when starting the engine as there is no oil pressure.
Almost certainly the boat has a neutral safety switch that prevents from starting the engine unless the shift is in neutral. If you already have the shift in neutral try turning the key to start and moving the...
You want a oil that is gas rated. Many 15W40 oils are both gas and diesel rated. Just make sure it's at least gas rated. There are a few that are only diesel rated.
You MUST have a marine starter. MUST MUST MUST. The are several companies that sell marine parts at a discount online. Pull the starter and look locally for a place that rebuilds them. They are there. Just need to look. They will do a better job than many of the starters you will find that...