Never mind I found it.
Primary fuel/water separator with drain NAPA 3123, 12 micron. Secondary 3124 6 micron. Listed as being for '82-'83 6.2L diesel engine in Chevy trucks. Add a 5 in front of that to get the Wix number. You will of course have to get the correct spin on heads for that. 3123 is a 1-12 thread, gasket OD 3.444, ID 3.100. 3124 has a M16x1.5 thread, 2.736/2.430 gasket. The base for the 3123 is a NAPA part number 4309, with 1/2" NPT connections. Not sure about the metric one though.
Birken