Installing modern seat belts in 69 Mustang

2-Jan-2015:
Nothing is ever as easy or straightforward as it should be for me. The stock seat belts in 69 Mustangs are a complicated 2-belt affair, with separate lap and shoulder belts. This was the first year Ford installed shoulder belts in the Mustang. I thought it was time for an upgrade to a modern style 3-point belt with the inertia lock retractor mechanism. The Scott Drake version has buckles that are very close to the original style, so it looks appropriate, even if slightly less convenient to operate.

Everything seemed to work well until I moved the seat all the way back – which is necessary for me. The seat interferes with the retractor as can be seen in the photo below. The only solution I can think of is to move the mounting point rearward, which won’t be trivial since the rocker panel is effectively a closed tube and structural member of the unibody.

14-March-2015:
I relocated the mount for the retractor using a bracket I welded up. I had to cut a hole in the inner rocker panel to fish it back into position. I pop-riveted the bracket in place and welded the hole back up.