You could parallel the two centre tap windings, you would have to separate every end and identify it with is companion other end and then phase everything before hooking up in parallel. for phasing, only connect the end of one winding with another and then measure the two open ends and there should be close to zero voltage, if it is double the expected voltage then use an alternative end of one winding and try again, when you get zero voltage, you can parallel both windings by then connecting the two ends that read zero voltage.
Clear as mud, I know!
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.