I NEED YOUR ASSISTANCE I HAVE A CHINA ROLLER Gt Union Gt3 Euro 4 Injections and need a new engine 139 QMB complete engines with carburetor are offered I can let such an engine install the carburetor away and for that install my injection system I do not know if this works because of the connections z,b, electrics, plugs etc. or can I drive with carburetor many thanks for your help with friendly greeting INDI