Pre and post fuel pump filter

[Jr]

Can anyone give me an idea of how many microns the pre and post filter should filter on a 5.3LS motor. I was going to run a dead head system with the corvette filter and regulator, but on the factory 5.3, the fuel is regulated in the fuel rail. Jus tso you know, I have a Walboro 255 pump ready to rock, but I have no idea about the pre and post fuel filters.

David