you are having a girl drive a station wagon as a first car? brave indeed!
you know the seats ALL fold down right?

okey dokey, if the ground is good, check to see if the temp sender on the head near the glow plugs is connected, and if it is, disconnect it and short it to ground. that should peg the temp gauge. if it does not move, then it's a bad gauge in the cluster.
OR it could simply be loose screws in the cluster. the screws give ground to the cluster via the center gauge. often the face is damaged, and the screws will not tighten. take it all apart, pickup the broken pieces of plastic where the screws go, and glue them back together. then clean all the parts that touch, and reassemble.
the lights don't work because the porcelain dimmer sucks. solder a jumper across the two terminals on it.