On my initial setup with my UCD & Saito 100, I had to lean the idle mixture almost 1 1/4 turns to get it to idle without loading up. This was due to the high tank location. It ran pretty well like this for many flights.
Then I moved the tank to the CG and put a small 2 oz header tank next to the firewall. It ran ok but not as reliable depending on the fuel level remaining in the main tank. So I added a Perry pump and presto, I've got 16 oz capacity with no problems even in the wildest attitudes and tumbles.
I was running a Saito 180 like this also, with 16 oz main tank at CG and a 4 oz header at the firewall, without pump, and that 180 just ran and ran, as long as the header tank was full, no problem with any attitude!