Always an interesting time when you start drilling holes in a classic vehicle. We did one door in this way just as an example of how to treat a cavity to which there was no easy access, like a chassis member. On the other door we removed the trim panel.
This is the cavity wax in the 500ml aerosol with the choice of nozzles and the extension piece with the spray rose on the end of the extension.
With the drill up and running a number of holes were drilled, this one in the end of the chassis member where it meets up with the wheel arch.
The endoscope makes it easy to see into a cavity.
Straight, flexible, lit or unlit. With mirrors and extension pieces or without.
This time drilling into the underside of the chassis member.
Further inspection of the chassis internals.