It seem that knee panels are a well known struggle for some builders. I perfected my technique for fitting them while working on my previous cars. My Sigma 150 didn’t have them fitted when I purchased the car and after my first track day with that car I decided they needed to be fitted after getting a big fat bruse on the right knee.

If you have fitted the exhaust, start with the non exhaust side, that little bit of extra access makes the job a tiny bit easier.

The panel needs some IVA trim on the edge, and a large rubber bung to be fitted. The IVA trim won’t sit straight on the edge of the knee panel if you don’t lip the bung over the IVA trim.

Next I glued the IVA trim, but not under the bung. I am using Loctite 37532 Black Weatherstrip Adhesive. Once dry I cleaned off using the excess with Auto Glym Tar and Adhesive Remover. This leaves the knee panel ready to fit.

The piping that is already partial riveted to the chassis but it has a little excess that need to be trimmed off. I used a strong pair of scissors. Now the piping sits flat, I could mark the holes, to do this I used a strong pick, to punch through the hole. The holes are drilled into the chassis tube so there is no danger of punching through the the outer skin.

With the piping marked I was able to remove it so I could punch holes into it. I used a hole punch tool to create a neat finish.

Now my top tip, using masking tape, I mark the position on the holes that need to be aligned with the holes in the chassis / side panel.

I also lubricate the panel below the masking tape with some rubber lubricate to help slide the panel into position. This panel does take some positioning. I have to go very close to the dashboard lower chassis tube, and has a tendency to slip down too low. It does fit, but I understand why so may break out the drill and make new holes, personally I have never found the need to do this.

Once you have one screw started you can use thats to align the rest. I got all the screws started by hand, but had to work them in slowly as the self tappers do their work.

I will finish tightening them when the side panel rivets are fitted.

Tool Used

  • Strong Pick
  • Pozi screw driver
  • Pozi screw driver to 8mm adapter
  • 8mm ratchet spanner
  • Hole punch tool
  • Scissors