Auto to manual conversion problem #1
Thread Starter
Melting Slicks
Joined: Dec 2009
Posts: 3,212
Likes: 638
From: Thunder Bay
Auto to manual conversion problem #1
So I've collected all the parts I can think of and now its time to start pulling the car apart in preparation for swapping my automatic for a TKO-600. Tonight I pulled out the steering column, instrument cluster, pedal assembly, and brake booster. Much easier than I expected, although I can see reassembly will be a challenge in a couple of spots. But I digress. I trial fitted a few of the parts to see how things will line up. and I realized there is no hole in the firewall for the clutch push rod to go through. So it appears I have to drill the hole. How do I know where to make the hole??? Some input from the guys who have done this conversion would be appreciated.
Pro
Joined: May 2008
Posts: 582
Likes: 9
I am not going to be much help, but I have completed this on my 1979about 6 years ago and a friends 1980 about 7 years ago. I remember there was a a rigid cover of some sort that had to be removed. The steel plate on the back of the firewall that has the holes that the booster studs go threw also has the hole for the clutch push rod. It seams like the fiberglass had to be cut out of that area. But again its been a while since I did this but I know the provision was there on both cars. The bottom of the hole is even with the bottom of the opening for the fuse box in the below photo. I can take a photo on the inside of the fire wall if it will help. Let me know.
Burning Brakes
Joined: Apr 2007
Posts: 1,039
Likes: 62
From: Kona Hawaii
My 76 had a circular plate attached to the firewall with three screws.Plate is removed then in it's place goes the rubber boot for the pedal rod..I used the speed direct clutch linkage.Makes for a smoother operation and better adjustments....
Thread Starter
Melting Slicks
Joined: Dec 2009
Posts: 3,212
Likes: 638
From: Thunder Bay
I am not going to be much help, but I have completed this on my 1979about 6 years ago and a friends 1980 about 7 years ago. I remember there was a a rigid cover of some sort that had to be removed. The steel plate on the back of the firewall that has the holes that the booster studs go threw also has the hole for the clutch push rod. It seams like the fiberglass had to be cut out of that area. But again its been a while since I did this but I know the provision was there on both cars. The bottom of the hole is even with the bottom of the opening for the fuse box in the below photo. I can take a photo on the inside of the fire wall if it will help. Let me know.
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Pro
Joined: May 2008
Posts: 582
Likes: 9
I did a chevy truck conversion about the same time....maybe it was the one I had to cut the hole. I was thinking about it and it and I think there was a plate there.
Yes that is the hole. Also the speed direct linkage as mentioned in the other members post is what I used.
The below is the only photo I could find of the linkage. If I get home in time tonight I will take a few more photos of the hole and linkage.
Yes that is the hole. Also the speed direct linkage as mentioned in the other members post is what I used.
The below is the only photo I could find of the linkage. If I get home in time tonight I will take a few more photos of the hole and linkage.
Racer
Joined: Sep 2002
Posts: 357
Likes: 0
From: Sayville New York
I just converted my 81 from Auto to 4 spd. The AIM showed me the location, plus I believe from under the car looking up at the firewall there was dimples for the screw holes and an indent where the hole should be cut for the clutch rod.
Le Mans Master
Joined: Dec 2003
Posts: 5,380
Likes: 415
From: N J
3 dimples on my 77 when I did mine too. It made it simple to locate. You may also have to drill a small hole as I did for the return spring as shown below. 
Edit: Now that I think about it, the hole was already there with a grommet in it.
Last edited by John 65; Dec 10, 2013 at 07:38 PM.
Advanced
Joined: May 2010
Posts: 50
Likes: 3
From: Flint Michigan
I had a linkage clutch at first with my auto to manual swap. The geometry was off just enough to negatively affect contact with the throw out bearing. Long story short I went with a hydraulic setup from American power train and it works perfectly! I wouldn't go any other way when doing a conversion.
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Thread Starter
Melting Slicks
Joined: Dec 2009
Posts: 3,212
Likes: 638
From: Thunder Bay
Thanks, guys. Once I knew where to look I could see there are three small dimples in the firewall. It appears to me that two of them are for the screws retaining the boot, and the other is the centre of the hole for the clutch rod. When I look inside the car, I can see that the hole for the clutch rod is in the two inner metal panels, but hasn't been cut through the fibreglass of the firewall. Should be pretty straightforward from here. Love this forum! 
