its pretty simple now that im thinking about it.
youd need a dpdt on/on switch to ground out the red or white wire. im not sure which one corresponds to the top coil so you could ground them both just to be safe.
put the red wire to the middle tab of one side of the switch. the top connection to ground. the bottom to the other switch as shown in the powerboost diagram.
then do the same thing on the other side of the switch for the white wire.
when the switch is one way youll get the coil split, the other way it will be as the normal power boost diagram.