WILDCRASHWILLY

Back on the Decath again.
Tried TBM numerous times for tech assist. Apparently customer service no longer applies to them as I have called four times and either left a message on voice mail or was told their tech asst. Guy was out and they would call me back. Never got return calls. In fact their is a thread on RCU about their terrible service. I bought this engine from them but no more. Learned my lesson.
Anyway, I found out about Dons Hobby shop from an advertisement in Model Aviation. I called him to order some metal machine tees they advertised and like the way he treated me. He offered numerous suggestions to my delima.
I would like to know what you guys think about the following.
I plan to convert the tank from a three line where I had a vent, a fill, and a carb line run separate. My carb line is about 20 inches long. Here is the change I'm planning. Go to a two line system. Put a tee in thr carb line about three inches from the carb and connect my fill line here rather than having a separate fill line at the tank. This will cause my carb line to be preloaded with fuel as my issue is fuel pick up anyway. Also, I purchased a metal Perry pump check valve, "rated for gas", from Tower. I plan to install this between the tee and the carb. Hopefully this will keep the gas from flowing back to the fuel tank when the engine is not running. And last, I think I can shorten the line overall by 2 or 3 inches to the carb without having to move tank. Has anyone else tried the chk valve approach on gas? I never have but I've been lucky I guess and haven't had a fuel draw issue until now. I think this valve might restrict the flow on a larger 80 or 100 cc engine but, I may be okay on this 40 cc.

Thanks for any suggestions you have given me to this point or any you add later.