Instead of using acetone, 1000 grit wetsand and scratchx polish to remove the green tint from the back of the gauges. Then use lighting gel in the colour you want. Then you can do custom stuff too (like make your redline numbers red, rest of them blue).
1966 Mustang Sprint 200--Wimbledon White
1998 Mustang V6 Coupe--Silver--RIP, Totalled by brother
2005 Mustang V6 Premium Coupe--Sonic Blue