Cart, see your avatar? take the motor off, level the floors where the consoles are and then shrink it to 12 ft. that's what I'm picturing.
Here's where the problem comes in with what you're wanting to do.
We've seen lots and lots of conversions on here. 12's, 14's, flats, V's , modified V's, decks, no decks, you name it, we've seen 'em all. The biggest downfall of all of them is weight. The hardware weighs enough, add all that weight laden wood and there's the achille's heel. Especially for those of us who fish electric water.
You say you want to take this (my boat):
and shrink it down.
First you need to realize why my boat is designed the way it is. V hull bass boats were built to provide the best possible high-speed ride in a variety of water conditions while not compromising the fishermen a stable fishing platform at rest. The boat designers accomplished this by pushing the boat width out wide enough and using the internal ballast (weight of the sucker, ie: fiberglass, hull structural members, gas tank). My boat is a 1986 Champion 184DC. The beam is 86". Champion built this boat in response to the Skeeter Wrangler, the first true V hull bass boat. The Champion 86" hull was actually a modified HydroStream Performance boat hull redesigned for bass fishing applications. The thing rides like a dream, one of the easiest and best performing bass boat hulls ever BUT
some people don't like them because of their tendency to roll if both anglers are on one side of the boat. I wouldn't call it tippiness, it's not that severe, it's just a nuance of the hull you have to get used to and a tradeoff for the great ride. Other Vhull designers have flattened out their hulls, like Ranger, which gives you a much more stable at rest platform but the big water ride suffers. The point I'm getting at is this. The V hull is probably the worst design for a bass fishing boat if the need for a smooth ride in big water isn't needed. In fact, it's the worst design and in your case with what you're wanting to do, probably not possible because you're wanting to remove the ballast of the hull which is part of what makes it stable to begin with.
Here, I think, is probably a better idea if your wanting some semblance to a Vhull bassboat but still have the fishing stability:
This Cajun (it doesn't matter the brand, all the manufacturers were making these) was the second revolution in bass boat design. It was an attempt at a Vhull bass boat. Notice the V slicing from the front to back but notice something else? Those side sponsons that ran up both sides of the hull.
These particular boats were around 74-78" wide, at least 10" wider than the previous old bathtub style, cathedral hull bass boats. The designers though, felt that a true V that wide would be too tippy so they added those side sponsons to provide stability at rest. Were these boats stable? You bet. Did they give a true, smooth, Vhull ride in rough water? Well, no. They were far better than the old bathtub style boats but those sponsons prevented the V from slicing through the waves.
If you were going to lighten the ballast of the bottom of the hull, I'd think this would be a better design if you're wanting to try and keep the thing looking like a mini-bassboat. Granted, adding the sponsons will increase the surface area of the glass and thus increase the weight of the boat hull but without them (sponsons), I'm afraid you're lightweight mini V hull would be tippy as all get out.