I have used the HBC custom cut reproductions that were already cut for Tachometer, and Clock/Fuel on a few peoples projects in the past and the savings in time is handy.
They use the OER reproduction dash carrier which is quite good in appearance and fitment. Sometimes you have to trim a bit the chrome edges but no big issues with it in general. I've gotten good at cutting the holes for single and double toggles for power tops and defoggers since they do not offer those custom options at HBC.
Yes it costs more then the standard carrier, and yes the templates are there on the back already or available at Team Camaro and yes you can easily chop out the parts you need by yourself but to have it arrive, unbox, mount your gauges and go, or only have to make one bowtie cut for the power top switch is great IMHO so I would buy them again no question especially for color interiors.