I feel having a marine carb for your own safety is more important than having it to avoid insurance arguments.

Anyone who has ever failed a fuel pump know first hand this is not an area to take any risk. Your safety is your one thing and the safety of the unsuspecting people in and around your boat is another.
Steve

I had a failed diaphram in a fuel pump in my cruiser year before last and thank my lucky stars it was a marine fp plumbed properly to drown the engine in fuel and shut it down. I had marine qjets with miter cut vent tubes puke fuel all over my intake and catch fire one time off a huge wake. Id never now run non jtubed carbs. A lot of the marine stuff is bs to make more money, but the jtubes and marine fuel pump dont mess with.

You won't have any "insurance" arguments unless you give them a reason. The marine insurance industry is laughable. Unless you do something absolutely nuts... like burn your storage building down while it's full of boats and then someone finds out it was because you were messing with a car carb on your boat... they just pay the claims. Just my personal experience as an owner of a marine repair shop for these past 30 years. The people they send out to "adjust" on claims usually haven't got a clue about any of the stuff going on inside or outside of the boat.

I will say, the difference between a Edelbrock Marine and a Edelbrock Auto comes down to 2 drilled holes and an extra seal around the accelerator pump. The marine carbs also get some sort of coating on the body but all of them use the same exact screws, pins, levers, plates, springs, etc. The throttle lever on a Edelbrock marine carb is drilled and tapped for a step-up screw, something never used in a boat but is in most cars. You can add the acc seal ($14) because the boss that it seats it is already cast into the (auto) carb top. I did a whole video on it with a marine 750 and a AVS2 800 side by side. I found that the AVS2 800 (auto carb) because of bowl venting (2 drilled holes) made a better marine carb then the Edelbrock 750 Marine. I made contact with an unnamed high up Edelbrock tech through email awhile back on why they didnt have a "certified" 800 marine (telling him I knew how little difference there was between the two) and was told basically it wasn't worth the hassle to get it certified today due to the costs, hassle of Gov regs and the low number of sales.
It really comes down to fuel bowl over flow. If it will flow over the top, bad or go down the throat, good.