just because the parts look new, doesn't mean they are correct. bosch or ngk plugs only, no platinums, bosch included. bosch or bremi cap and rotor, no exceptions. karlyn or bremi wires, no bosch, no oe-which is bosch in the mb box. these items tend to be exspensive and there's lotsa cheap imitators out there.

perhaps the coil is weak. you need to see if the available kv is strong enough for a cold start. needs a scope to check that.

could be a fuel issue, maybe too lean or control pressure too high. there's lotsa variables to a hard start issue. good luck, chuck.