Maybe this time! I used the clamp-on microphone pickup and started to go through suspension joints, but got nothing. Just for the heck of it I clamped it on the RIGHT FRONT BODY MOUNT and it was chirping away. I pulled it out and wire-brushed all the rusted metal surfaces and greased up all the contact areas. I put it back and no detectable sound audibly or electronically. It may be coincidence but this was distorted very slightly when my son had a minor accident.
I will keep tabs on it before I celebrate. My soundproofing project would have made this squeak stand out even more against a lower noise background. We'll see and thanks for reading,
Dave