The standard 2CV coil mounts are slightly flexible plastic that don’t grip the coil very tightly allowing it to rattle around. Additionally the mounting bolts on mine weren’t in the best arrangement with a cross head screw on the top meaning access was blocked by the coil itself.
When doing the initial service we had managed to loosen the bolts sufficiently to get enough play to remove the coil from the mounts without removing the mounts from the headlight rail. With access to the cross head screw I was then able to get the off side mounting bolt removed. The 7mm nut on the near side made some movement but the rust was so bad that the – already worn – cross head soon rounded. As I was replacing everything anyway I hacksawed off the head which did the job.
The new rubber coil mounts come with rust resistant screws and the bolt head under the coil is held captive by the mount itself. Fitting them is pretty straightforward but I’d recommend fitting the near side mount first (leaving the bolt loose) before fitting the coil and the off side mount. This allows you to access the slot that holds the bolt and make sure it’s fully down thus ensuring it will emerge from under the light bar.
The rubber is sufficiently firm to hold the bolt whilst you tighten the nut. When fitted the coil is now held firmly by the mounts preventing it rattling around.