I did a leak test in the injector return lines results were,
30 sec test

Cyl 1 50
Cyl 2 55
Cyl 3 70
Cyl 4 70
Cyl 5 65
Cyl 6 50

So cyl 3 & 4 are 40% more I assume this is not ideal????

I have 2 spare cleaned injectors on hand so might replace them if needed.
I pulled 3 & 4 injectors and found the nozzles with crud, they were only cleaned 6 months ago, so maybe fuel quality is an issue.