Re: v6 carb upgrade
The Edelbrock 1409 will work, but you will need a new throttle bracket, intake manifold, fuel line and flame arrestor. Edelbrock sells a kit to change the stock jets and rods to a 4.3L configuration. I believe the increase in HP is about 15-20hp, but check the Merc specs for the 4brl model of the same year. It will probably improve your low-end slightly, based on the smaller primaries of the 4brl, compared to your 2 brl. You will see most of the gain in your wot mph, which should increase a few mph, but depends on your hull. Only you can determine if the money is worth the gain. Keep in mind that you can ebay the old parts.
