RE: Inverted OS .46 Floods
gaRCfield is quite right and the tank is too high to avoid syphoning and hydrolocks continually. It will never function properly with a conventional glow engine fuel system without a regulated/pump system such as Dave mentions. That's the bottom line and it does not matter if that's the way the manufacturer has set it up. Fact is a lot of product these days may not even have been properly flight tested and you cannot always count on the 'instructions'
Here are your options:
1. Use a smaller (shorter) tank so it does not protrude into the wing compartment I realize its the wing that is the reason you cannot lower the tank lower.
2. actually cut a channel into the top side of the wing that will allow you to lower the tank a little (this without cutting into the main spar or the leading edge spar. It sounds like a lot of work but its not really and I have done this successfully several times on pylon racing warbirds.
3. Go to a regulated/pump system. These may be rather expensive not sure or not sure of the current avalibilty of the Cline units.
4, Last options is to simply rotate the engine ninety degrees, This will raise the carb likely enough to stop the problem. A bit more work but costs nothing and you will have to make ample cutouts on the cowl. This last reason is what causes so many problems with new folks and it that complete unwillingness to make ample cutouts or holes for things such as needle valves (high and mid range) cooling air both in and out or simple letting a cylinder head protrude making easy glow access.
If you are interested in option #2 I will make some more photos of the wing cutouts on one of my ships and how its done. I don,t think I have any in my files highlighting that.
John