Hobbyist needs Help!
simulate this circuit &ndash; Schematic created using CircuitLab

The left side is shown wired for 230V operation,if you want 115V use the other wiring parttern shown on the data sheet

The right side has a switch to select 3.15 or 6.3V output 
use a DPDT switch, you can use a centre-off DPDT switch here if you want.