Any of you that followed my new boat outfitting thread fishwrecked.com/forum/another-caribbean-reef-runner  here, may have saw that I fitted a stainless seat base frame, with an eye to putting a fridge under it--well, the original idea was an icebox, but it just grew into a fridge, as they do.  Ran out of time to do anything before the big trip, but got into it later, and used it on the Shark Bay 4 day cruise a few weeks ago. Worked a treat--in fact you need to run it at the warmest setting in cool weather. Leave the milk hard against the plate overnight, and it will get slightly slushy, but the alcohol was fine, very cold and frosty . it ended up just over 50 litres capacity. It can be slid out a bit as a third seat, is not in the way when slid right in, and the lid is split so you don't need to slide it out at all for quick access. 

Why didn't I just buy one? Well, it would have been cheaper, BUT--

1. Everything will rust on a car fridge used at deck level on a boat. Nothing can rust on this
2. Electrics are all at deck level on a car fridge, I raised all mine up into the box section that sits forward, under that ali checker plate,  you can hose around it
3. No fridge slide nneded, and you can access it without sliding out , due to split lid
4. Better insulated than any car fridge, seems to come  on about  once an hour for a few minutes, so stuff all draw on the battery, and Andersen plug connection.
5. I made it with a bung, so it's a hose out to clean. 
6. All components are replaceable. You will get to the stage on a hard-used car fridge where you have to bin it, not this one. 

The fibreglassing isn't the prettiest job I've done, as I elected to use an old icebox that had been partly cut up for another project, and grafted a marine ply box on the end for the fridge gear--new materials all around would have been tidier, but it does the job.