I know of several Aircraft using the same sump you have. Carl Denk's Cozy 3, and Steve Volovsek's beautiful new Long-ez are flying examples. I have on my Long-ez project. Gary Hertzler (the go fast guy) has a custom sump with fuel servo on the firewall side as well. Making room for the fuel servo by cutting a notch in the firewall is not a problem. One factor to consider is to provide firewall-equivalent protection to all areas forward of the firewall after the notch is cut. I have a sump tank in the "hell hole" area, so it was a critical factor for me.
Another issue to consider with that sump is the location of the intake tubes. The internal intake path through the sump has a different orientation than more standard sumps, causing two of the intake tubes to exit the sump at a much lower waterline. On a Long-ez or a Cozy III, this means the tubes protrude into the slipstream and the cowl will require work to accomodate them. This may not matter on a Cozy IV or a Velocity.
If either of these issues seem like a show stopper, you can always swap out the sump for relatively few dollars. I decided to keep mine, but will probably build a custom sump after I fly to change the location of the intake tubes after I fly.
