FWIW, I have used my 8274 completely submerged. Not so much as a hiccup. Worked great.
I have a HF 8,000lb (road gear?) winch on a receiver mount. It's heavy, but not horrible. Not sure what the weight is. My setup works like this: I have anderson connector setup on the front, so I can just plug and play. No 12v power to the back. What I do have is a 20' set of 4ga jumper cables with an anderson connector end. So for jumping I don't need to open the hood. Just plug them in. But if I need to winch in reverse, I put the winch on the back, then jumper cables up with the alligator clips onto the batter poles. Not ideal - but it works. or I could put the winch on any other vehicle as well.
On my new 4runner i'm going to have to mount the winch permanently as it will be hidden behind the front bumper. I've considered adding a HF 5,000lb badlands on a portable setup for rear pulling. They are cheap - relatively - and pretty light. And in my general experience backward pulls usually aren't going to require the full 8k lbs. Often just a little tug is all I need to get back a few feet.