Torklift mounts are very nice. You will not be disappointed. They bolt up to the existing frame holes in most cases and are custom made for each make and model.
You can make some if you are handy with welding and have the steel. Do not weld on the truck frame between the axles (or behind the axles if you tow).
If you are handy then you do not need us, so guessing you will be buying. Sometimes used ones are out there if you have a truck that is a few years old, it is worth a look. I have some 2nd Gen Ram ones just sitting in a bucket unused currently, unadvertised...
The benefit of having the outlet in the bed is that it shortens the distance from the alternator to the camper battery. This helps reduce power loss. Going all the way to the bumper, then back up to the battery (usually at the front end of camper) could be another 15 feet or so. However, for just keeping the battery topped off this distance is fine, just do not expect to chearge a dead battery very fast. If you have solar then the solar would be doing the bulk of charging when in the sun.
You can modify your truck trailer plug (move to front of bed), or you can modify the TC trailer plug location. I did the TC location and put it at the back, under the camper, where the truck's outlet is. This is only for the lights (flat-5 plug, not the charge). I can load TC then plug it in. I can inspect the plug with truck loaded even. I can unplug it then plug it back in with the TC loaded also. The only benefit of having a front TC plug is to get the TC battery closer to the truck alternator, so I ran a separate plug and socket in the bed with big wires and big connections for the rare occasion I would need to charge from the alternator.