Brothers of The Benz,
The biggest battery that will fit in your case, if you still are using the underhood position.
The strongest in all capacities you can find.
My 1987 300E currently has an Interstate MTP-93.
It's thier mule of a battery for a Mercedes.
Now if we could just find a good alternator.
Happy Trails Beep Beep from The Spiderman in Houston.
P.S. I travel with an extension cord and a battery charger.