69-72 emergency brake on a 67-68

[AusMarty]

Has anyone done this convertion without cutting up the firewall ?
I know the firewall is different, cutting my firewall isn't an option as the truck is finished

[tantrumpipeline]

I don't have an answer just want to know as much as you for my 68 as well

[Racinaround]

If all else fails i used a Lokar one ones and it went in nice

[basemodel67]

Also interested.

What about mounting the 67-68 style handle to the side of the floor hump?

[LostMy65]

So, you guys prefer the pedal type over the handle type?

[HeavyD]

Yes I have always liked the pedal better.

[Zeroman]

I have added the 69-72 pedal assembly to my 67 cab on my build. Still working on the build, so the truck is not road worthy yet, but soon will be.

I swapped my rusted out 70 cab for a 67 cab. BTW, this is one of the things I have had to "adjust" because the 67 cab is unique in several ways.

So there are just a few things that need to be done, but since you are already past the paint stage, one would be extremely difficult, and would cause some repaint. It is the welding that will get you.


I will try to post some pics later tonight.

It really helps if you have a 69-72 stripped cab to get dimensions from, which I did at the time. I may still have my notes, I will check.

When the GM engineers went to the pedal Emergency Brake assembly they had to reinforce the firewall by redesigning the firewall to add strength to the area where the pedal assembly would be bolted. The 67 firewall is flat so adding a raised section which is raised towards the front of the vehicle accomplished that. The foot pedal assembly, therefore, would be about 1/4" - 5/16" longer than if there was one for the 67 cab.

I wanted my firewall smooth, so I mapped out the location of the two studs which protrude from the front of the pedal assembly, and the rectangular hole for the cable. To make sure the area was strong enough to take the force of operating the pedal we added a 2" wide x 8" long plate to the inside of the cab straddling the location of the bolt holes. Drilled the holes for the bolts in the firewall. We actually drilled and tapped the holes in the plate so the bolts were fed through the firewall and threaded into the plate, then welded, which should increase the support of the bolts. Welded the plate to the firewall, then welded the bolts into the firewall facing the back of the cab, welding both the outside and inside of the cab. Then, ground everything smooth on the front of the firewall.

You could just drill the holes in the firewall, and install the pedal assembly as intended with the studs protruding into the engine compartment, but reinforcing the firewall would be the challenge.

Cut the new rectangular hole for the cable.

I removed the studs from the pedal assembly leaving two holes to match the new studs on the inside of the cab. It is tight getting the nuts on the studs but it can be done. My cab was bare when I bolted the pedal assembly in the final time so I had no obstructions to worry about....wiring harness, cables, etc.

I ended up just grinding off enough of the back end of the pedal assembly so it would fit under the dash and line up with the area to bolt it up. This results in a "slot" on the back end of the assembly for the bolt to go through instead of a hole. Then I just marked and drilled an appropriate hole on the bottom ledge of the dash. I think I did have to grind some of the backside for the lower lip of the dash to allow the back end of the assembly to slide right to left into place.

I did have to "Adjust" the pedal arm so the it looks vertical as it sits, but I am not sure if this is due to the intended design, or if the pedal assembly I had was bent to begin with.

I installed the stock 69-72 Front Emergency Brake Cable which seems to fit well, and matches up to the 69-72 Intermediate Cable.

If you have the Firewall Insulation(cardboard/jute) you will have to cut out the area where the pedal assembly attaches to the firewall, then reinstall.

The pedal is a little "tight" when pushing it with my hand, but I have not operated the assembly with my foot as I have not installed the seat, yet.

I think that is about it. If I think of anything else I will post.

[Andy4639]

I have no other reason to post this but to say Leg power is stronger than arm power so I would think the later park brake would be better in my opinion.
I just took the handle out of the Ramp Rat because it was froze up and the cables under the truck are gone it didn't work so at some point I may add the foot brake.

[Zeroman]

Pics.

1st pic is smoothed firewall

2nd you can see the studs with the nuts

3rd is the bolt holding the back of the assembly to the bottom of the dash

4th is showing the rectangular hole for the cable and you can see the plate

5th shows the back of the assembly where the slot is for the bolt/nut

You can also see the adjustment to the insulating kit