Jeep Repair: MPI fuel injection kit for older 258 ci jeeps, distributor shaft, wire trays

Question
I've run into 6 different owners with MPI kits and including myself
we are all haveing problems with what appears to be vapor lock.  
With high ambient temps (85)degrees plus. This is also sometimes
associated with high speed driving at high temps. Any guesses!
Thanks...

Answer
I just remembered some of the TSBs I did run across on older jeeps.  There was alot of them regarding distributor shaft play causing poor driveability as well as cross-induction by having the wires not routed properly.  The only time the wires should be running side by side is if they are in wire trays.  Also, should there be a need for them to touch make sure they intersect at 90 degrees or so instead of running side by side with nothing more than the standard 8-9mm insulation found on the wires themselves.
Doug