HELP 79 G1 solenoids

[owll]

Cart was turning slowly in reverse and finally wouldn't turn over in forward or reverse. put a replacement reverse solenoid on that I had, same kind all terminals on front, and it worked for a day and quit. Put other solenoid on, forward, and cart will run in forward but when put in reverse solenoid clicks once and pos post on batt. arcs and smokes then nothing works, forward or reverse. If you take off pos terminal on batt and put back on it will run in forward but as soon as you put in reverse and press gas pedal it clicks, arcs and then nothing in forward or reverse until you take off pos terminal. anything I should be looking for other than the solenoids?