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**pjmoreland** · 03-06-2023, 02:09 AM

One of the bigger holes is for the speedometer cable. I'm not sure what the other big hole is for. My firewall has an extra hole like that, and it just has a plug in it.

The two smaller holes may be for a factory tachometer (brown) and a TH400 kickdown wire (pink).

03-06-2023, 02:09 AM	#2
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,349	Re: Mystery holes in firewall. One of the bigger holes is for the speedometer cable. I'm not sure what the other big hole is for. My firewall has an extra hole like that, and it just has a plug in it. The two smaller holes may be for a factory tachometer (brown) and a TH400 kickdown wire (pink).