Need the s/n's of both. Water pumps and cylinder heads are different as well as some water piping between the D330C and 3304.
I will try to get those numbers and get back, and thanks for the reply.
Old Magnet, the d4 is 83j2548. I don't have the exact number off the 941 but I think it's a three digit number. I don't know when I'll get to see it again.
83J2548 is definitely a 3304 and the early 941 89Hxxxx has a D330C. There have been swaps between these engines without to much difficulty. As mentioned water pump connection/location is different and some modification to front motor mounts may be required. Radiator top connection may need to be modified.