How to drive eight PIN diodes in parallel with 90 mA current using Arduino Uno R3

I don't think that I have a way to ensure all PIN diodes will conduct identical currents. How much of an issue is this?

My confusion is that I expected the current driver to be between V1 and R1, but FET switches seem to want to be between the diode and ground. I have seen papers that do what I am attempting to do, but I am unsure how to drive 90 mA.