Mysterious Holes in firewall

Racefan · #1 01-14-2005, 10:27 PM

Anyone ever seen anything like this? As, hopefully, you can tell these holes are just above the throttle linkage and below the wiper motor. Maybe to get sending units through the firewall for aftermarket gauges?

DjD · #2 01-15-2005, 05:07 AM

Get ahold of copy of the '68 Factory Assembly Instruction Manual, AIM for short and you'll find firewall drawings with all the holes shown...

Mark_C · #3 01-15-2005, 07:20 PM

How big are they, look to be about 1/2" diameter? Nothing stock goes thru that location, that big. Some stuff (2 holes) come thru in that dimpled area just under the wiper motor, but their supposed to be .185" in diameter

Racefan · #4 01-15-2005, 08:08 PM

They are about 1/2" in diameter. When I got the car, they were covered by old duct tape. Didn't even occur to me that there might be holes under there! Now not sure what to do about them, patch them or leave them? I think my big block will disguise them pretty well after putting some sort of patch over them.

DjD · #5 01-15-2005, 08:43 PM

On the AIM for '69 it shows a .920/.940 dia hole to the left of the upper part of the steering colume cutout for RPO M20 transmission. The speedo cable is routed through the firewall there. I know this is not a '69 but if you had the right AIM to reference you wouldn't have to guess...

**scuncio** · #6 01-15-2005, 09:10 PM

I have seen hoses about that size for aftermarket A/C units...something to consider.

JChlupsa · #7 01-15-2005, 10:36 PM

from the 68 AIM

NCGuy68 · #8 01-16-2005, 10:49 PM

I don't see anything in the 68 AIM that calls for 2 holes that size in those locations. Looks like someone got happy with a hole saw for some odd reason.

Patch them the best you can and carry on with your project.

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