how small micron filter should I use?

[360moparjunkie]

Want to put single in line spin on filter before my regulator on my modified 73 swinger.
There are filters out there from 10 to 100 microns.
I have a large electric holley pump on 360 cid w 670 cfm carburetor w 140 shot nos.
Fuel line is minimum 1/2"
I only want to use one fuel filter for this system.
Thnks.

 

[flyfish]

After the pump, I use a 40 micron. The 100 micron filters are good for before the fuel pump (between the fuel cell and the pump)...but I don't use one.