I've ditched my instrument cluster for mini gauges on my '77D. There's now no place to mount my stock ignition switch so I've sourced a steering crown & switch from an 80's model XS that has mounting bungs for a switch. Wiring looks different across the switch plugs however. My current switch has 5 wires into plug & newer one only 3. Is there a way to make these compatible? Picture attached. Thanking you in advance!