Swapping a 300D IP with a OM606 IP?
 

Would it be any way possible to swap a 300D IP with a OM606 to make gains in HP? If so, I know there are 6 fuel injectors due to the 6 Cyl. engine of the 606. How would I be able to bypass that with my 5 Cyl. 300D?

300Ds came in 5 and 6 cylinder varieties but assuming yours is 5 like you mentioned you need a 5 cylinder pump as a 6 on a 5 will only be timed correctly on cylinder #1. If your engine is the OM617 then OM60x pumps won't fit on either

My 92 300D has the OM602 engine in it.

You cannot use a 6 cylinder pump on a 5 cylinder engine period. The camshaft timing in the pump is wrong and there is no way to "bypass" it to make it work on the 5 cylinder. A 5 cylinder engine requires a 5 cylinder pump.

OM602 should have a M pump, 5.5mm elements. You can buy someone's surplus 6mm M pump elements and have a shop swap them in and calibrate the pump.

It'll run you several hundred dollars all together.

Just get a 605 pump from someone in Europe

Would be cheaper to add an EGT gauge (which you'd need to do anyway), turn up the turbo boost, and turn up the fuel by adjusting the IP governor. You'd also want to advance the IP timing a bit, maybe advance the camshaft timing a bit as well.

Modest gains are possible for little cost.