I have not used the products below but have used something like them in the dim, dark past. Maybe this will give you some ideas?
https://www.sciplus.com/conductive-wire-...BCABEgKEJfD_BwE(oops! bad link)
Try this one...
https://www.ebay.com/i/153790155322?chn=...BCABEgLb-vD_BwECheck with a local ham/amateur radio type and they may also be able to help with ideas and/or another way to help.
Paul -