300ex Reverse/neutral wires in motor

First..thanks for the help from all of yall throughout my ??'s on the forum...got hole in case fixed and i finally got my beast to fire/crank/idle for the first time in more than a decade...now I'm having problems with the wires on clutch side of motor where two wires go in..i loose power at switch then I wiggle wire where goes into motor and bam..it fires up..but sometimes it just pops and I loose power..and if i disconnect/connect batt cable and neutral light comes back on..wiggle wires once more and it starts up again..any ideas on what's going on..