I would follow Benzmac's advice to fix it right, fix it for good and not modify your Benz.
Check all the wiring and replace the starter with a certified Bosch rebuilt. I have tried other starters and alternators, and have found it to be false economy to buy anything else.
'84 Euro 240D, 523K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in