Seat Installation Instructions
These instructions are for installing a GTM seat with ‘side sliders’ and David Borden’s mounting brackets. I’m using seat sliders from FFR and only 1 side has a lock. The seat feels very good using only one locking side. I did all the work before adding the carpet and the aluminum floor in front of the seats. This allows easy access to everything for mounting. If the aluminum floor is already installed, it is a little harder to mount the front brackets to the x-bracing.
I’m only installing sliders on the drivers side as I feel it isn’t as important for the passenger side to move.
When installed and in the ‘all the way back’ position, the upper part of the seat will hit the fuel tank cover, but the lower portion of the seat back will be several inches away. After the seat with sliders and brackets are installed, the angle of the seat can be changed some because the brackets are slotted.
Start by removing the seat cover and marking where to drill the mounting holes. Place some masking tape over the sides of the seat in the general area where the holes will go. For the front holes, measure back from the front of the seat 3.5” (not the padding, the fiberglass). Then measure up from the bottom of the seat 7/8”. This is the front hole.
My sliders have mounting studs on 11” centers. Measure back that amount and then up ½” from the bottom of the seat.
The rear hole location.
Measure the width of the seats at points that the seat track studs go in. Mine were about ¾” wider at the back, so I added about 3/8” worth of washers at the front (see pictures)
The FFR seat tracks that I bought, come with hardware, but
not 5/16” carriage bolts that you will want to use to
I also cut about ¼” off the studs at the rear of the seat sliders so that they didn’t stick into the seat too far.
Front slider mount.
Rear slider mount.
Once the sliders and brackets are attached to the seats, place the seat in the car and locate it where you want it. I moved my seat inward towards the tunnel to maximize my head to outer halo bar clearance. The front brackets should line up over the x-brace in front of the seat. The rears are easy. Because I moved the seat inwards, you may notice that where the hole is in the bottom of David’s aluminum brackets are not the same side to side. Since I didn’t have the aluminum floor panel in front of the seats in place, I was able to put vise-grips to clamp the brackets to the x-brace. I was then able to sit in the car and even slide the seat forwards and backwards.
I then traced around the brackets with a sliver Sharpe. Then remove the seats from the car and the brackets from the sliders. Place the brackets on the floor of the car and drill the holes.
I recommend putting the seat adjuster lock on left side of seat. It faces down for clearance reasons. In this orientation, the lock lever is pushed down to release. Notice that it would hit the floor unless it is bent.
The pictures in the car show it after it was bent. In the picture above, it is the black cap on the rod right at the front of the seat (also, right where the blue tape ends).
Now bolt the completed assembly to the floor and recheck all your clearances before refitting the seat cover.
The seat angle and height can be adjusted a little because David’s seat brackets are slotted.
Now it is time to refit the seat cover. Remove the sliders from the seat. Refit the seat cover tightly over the seat back
Put cover on completely to make sure that it is in the correct position. Then unsnap the front panel so that you can reach your hand in through the front and back to the holes drilled in the side.
An awl would work well to push through from the inside, but I used a mini-philips head screwdriver. I then cut a small disk shaped piece out of the seat cover with an x-acto knife to fit the stud on the slider.
Put the sliders back into place and reach in from the front to tighten the nuts on the slider studs. Although I don’t have a picture to show it, when you slide the seat all the way back, the slider might dig into the seat cover at the front. My seat cover had enough stretch in it press the seat cover in close to the seat in the area that the seat track would contact it. I used a short ¼-20 button head to pull the seat cover out of the way. I also found a rubber isolator in my left over Corvette pieces that worked perfectly to provide a softer contact under the head of the button head bolt.
Here are some pictures all the way back.
And all the way forward.