We opted to retain the original frig in our 58. I specifically wanted electric (12V & 120V) with no propane. That led me to look at marine equipment. I settled on using a unit from Isotherm. The components come to you in pieces, but it is pre-charged with fittings that allow you to complete the hookup without leaking.
https://www.defender.com/product.jsp?id=5484050
Ours is a Krefft frig (German), it was a great size and sets off the floor in a cabinet so putting a newer frig would mean altering the cabinet. This is what the orignal unit looked like mechanically. It is very heavy.
The Isotherm evaporator is rectangular and was very close in size to the original freezer so I could retain the freezer door (inside the frig).
The compressor is now above the frig in a storage area of the cabinet. The wall unit to the left is the controller that automatically will switch from 120V to
12V. It defaults to 120V so I have a receptacle that is shore power only next to it. The item above the receptacle is the temperature control/off rotary switch.
The lines for the evaporator come out the back of the frig and are straightened out to go up.
I removed the rear extension on the body since we didn't need it. (compare photo 1 to photo 4) Unfortunately it didn't allow me to recess the entire amount (roughly 4"), but I did lose about 2" of overhang past the cabinet front face. So less is out past the cabinet face.
Original:
Revised:
I also added additional rigid foil backed insulation in the spaces between the cabinet and the frig. 1" on the sides, 1" on top & 2" below.
Part of wanting to eliminate the propane was to eliminate the lower venting through the floor/belly pan. I still get circulation for the compressor cooling, but the air originates in the trailer and is aided by an additional fan below the original frig roof vent.
We also went solar (4 - 100 watt panels and 2 160aH Lithiums) so having 12 volts while traveling is not a problem. I know a lot of people run propane while traveling, but it is not in my comfort zone to do so.