Tjp 70 Cuda here's a couple of pictures I've found online. The fuse box and bulkhead appear not to connect.

The fuse box looks to be feed from 2 wires coming from separate harness that plug in to lower terminals.


The for sale harness lets you hover over it to see it more clearly.

https://www.partshound.net/product/...y-oe-dash-harness-wcorrect-20-tach-wire/


Back of fuse box

https://timschallenger.weebly.com/blog/back-side-of-fuse-block-after-re-work