I am going to pull the trigger soon for the exact same fitech setup with the command center for my car. I'm sick of chasing the tune on my car. And I have the vapor return line on my car too.
I was urged that running a ground to the unit would be a good idea. Shown is the one I used, I got it at NAPA and I did have to enlarge one hole slightly. This fit nicely from a carb stud to the back of the head on a smallblock
I was also told that one or two users had codes that they eliminated by shielding wires. Shown previously is what I used to shield my wires. PM me if you need a source.
I also found the straight vent nipple to be awkward so I bought (what I think is) a 5/16ths 90 degree hose barb 1/8th male NPT
Pay close attention there's an arrow on the filter to shown direction of flow.... and one of the illustrations has the filter backward