[Eric71T37]

Hi all,

I have what is apparently a GP rally gauge/speedo cluster in my '71 T-37. I am almost certain I got it out of a '71 GP in a salvage yard long ago. It illuminates blue, while my in dash tach illuminates white (as apparently LeMans/GTO gauges and clocks/tachs should). Does anyone here know what makes GP gauges illuminate blue? Is it the light blue paint inside the metal can and on the back of the plastic bezel? Or is it blue plastic lenses that somehow affix to the inside of the cans? Any help appreciated. Bottom line is I like the blue illumination and I'd like to make my tach illuminate blue to match.

[ssj71]

Inside of the socket holes you'll find blue plastic lenses that the light has to pass through to illuminate the gauges. Those blue plastic lenses are tacked in place from the factory via melted plastic nubs.

[Eric71T37]

Thanks ssj. Here is a clock I took apart, along with a blue lens that did NOT come out of this clock. You are saying these blue lenses would be attached to the inside of the metal can? Maybe I can attach the lenses inside my tach to match my gauges...

[ssj71]

Yes, they'll attach inside the metal housing to where they'll surround half of the bulb after the bulb is in place. The bulb hole in the can will actually consist of the large hole for the bulb and two small holes for the blue lens. Nubs on the blue lens were heat tacked into those small holes on each side of the large hole.

[Eric71T37]

So the can pictured is not from a GP clock? Or, in other words, a GP tach or clock can is different than a GTO/LeMans can? Thanks for helping me get to the bottom of this.