The fuel injection is fixable - just be safe, wear gloves, and relieve the fuel rail pressure before you take it apart (hint - look for the little black cap on the fuel rail for relieving pressure - cover it with a paper towel to keep it out of your eyes and from dripping).
The rust....everything rusts. Its a matter of degrees and replaceable parts, and jeeps have lots of those available.
Good luck. I dig mine, even when it's yard art and can't move under it's own power. Its so cool getting it back on the road.
Current - 1993 Wrangler 2.5 - mostly stock
Previous - 1989 Comanche Pioneer 4x4 Long Bed/Metric Ton Pkg
4.0, AT, D44 w/ Trak-Lok RIP