I have owned 2 digidash GL-10's One was an 86 with the orange dash and one was an 87 with the green dash.
Opinion #1. DONT SWITCH IT
Opinion #2. If you choose not to listen to opinion one, at least use the green dash. Its FAR easier to read and generally more reliable.
Fact: You will lose your oil pressure guage and voltmeter. The other guages will be less accurate.