NA IP is apparently a little easier.
"I used a pedestal from a n/a diesel and drilled and tapped a standard compression fitting in order to use a mechanical oil pressure gauge. The pedestals are readily available. Two stacked together would allow easy fitting to a TD pump. One works fine for a n/a pump."
Talking there about the IP OUT fitting.
"Pressure in pump MUST be 43.5 Psi at 1000 RPM engine "
"Pressure at 2000 Rpm -about 75.4 Psi"
There's also a flow rate that is important to test.
All the information here:
internal injection pump pressure