I'm trying to straighten out some wiring to my tachometer from the PO. Unfortunately, I have no idea how much of the stock wiring is in place because the PO put in a Getty 911 dash.

I have two round lights at the top of my dash. The blue for my high beams. I'm pretty sure the left one (orange) is for my turn signals. Should this be a black insulated 2 post light holder or a single brass post holder?

Many thanks.
Dan