Two spades = switch pitch. So, you will need the detent that shifts the gear down and switches to high stall under heavy acceleration. There should also be a switch on the back of the accelerator rod by the firewall. This switches the converter to high stall at idle so it does not creep in gear. The wiring was different year to year meaning you will have to adapt the wiring from another year or find the switch and wiring from your year. Maybe try Ebay or put an add in the classifieds here?