electrical

Do you mean you get major sparks when you try to connect the last battery cable? Follow the positive cable to the starter and look for any place it's grounded, particularly where the terminal is bolted to the starter.

Remove battery cable from the starter motor, isolate it from ground and see what happens

Replaced starter. I had to jump start it, started with some difficulty. was running fine for about 8 to 10 minutes, I pressed the gas pedal and it died. The battery is approx. 5 yrs old, should I try a new battery or just charge this one?

Sounds like you might have a generator problem. After you jump-start it, use an inexpensive digital voltmeter to measure the battery voltage while the engine is running, then again after the engine is stopped. With it running, it must be between 13.75 and 14.75 volts. With the engine off, a fully charged battery will read 12.6 volts. A good but discharged battery will read closer to 12.0 volts.