Good luck gettin the wires off in once piece, better budget a set of new ones along with the plugs. I did this on my chum's 300E and we ended up having to chisel down the ceramic on the plugs to get to the head of the plug.
His haven't been changed easily within 10 years. Cap and rotor are a must for the M103 to run well.
Aside from that, run a can of Seafoam through the top end. Consider changing the fuel filter too. Maybe pick up an air filter while you're at it, flush the PS then toss a new filter in there too.
Eye the fan belt and the fan clutch.
Maybe she'll cook ya dinner and more...
