Any tips installing DSE dash insert in 69 Camaro

[rocketrod]

As one of my fall/winter projects I amd going through the interior, which includes installing DSE dash insert with seven Autometer Ultra-Lite gauges. I will be making a custom wiring harness for the install. I don't expect this to be too difficult, but are there any helpful tips/tricks you can pass on? Anything you would have done differently?

Thanks in advance