It's super easy to install 5" autometer gauges in a 67-68 dash. Drop the steering column, remove all the screws to the "pod" then disconnect the electrical and it will pop right out.
Then undo the screws holding the metal gauges to the plastic "pod" and you have the shell.
From there slide the speedo and tach through the front, and bolt the brackets to the back. Wire it up and put it back together and- PRESTO!! Custom gauges. I did this in my 68 in about 25 minutes. i used Auto Meter Phantom gauges with electric speedo so it would work with my VSS on the T56.
1968 RS/SS Camaro w/ 94 vette LT-1 and T56 six speed, Cal-Tracs, Baer 12" crossdrilled brakes 17" rims, ect....
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My 68 with LT1 and T56</A>