Looks like a "fixer-upper", a little rough but...
https://boone.craigslist.org/cto/5560901132.html
How many of us have really blown a head gasket on a 3.5L? Maybe a leak in the coolant bypass tube and/or poor coolant maintenance could give you the old "milkshake mixture in the overflow bottle", and the temp gauge issue, well break out the soldering iron.
No more responses, you may have hit the nail on the head.Hell I have an auction business and sold non-running vehicles for more. Just thinking, but given the 10-20K most of us add in upgrades for 4 wheeling, you might be in the wrong hobby.