Firstly sorry if this is OT guys but you do seem the best people to ask.

The part of London I live in has rubbish ISP speeds (4 mbit) and I have
been offered an old Relish.net router which is a Gemtek WLTFSR-115GN, I
know some of these have external aerial sockets (US ones I think) but
the version I will get does not have any external sockets, so it's a
case of go inside and try to figure out some way of connecting an
external aerial, now the reason I need an external one is I am right on
the edge of their coverage and only get a single bar using just the
router, I do have some images of the inside of the router so I will post
the links for them later, but I was just wondering if anyone has heard
of this being done in the UK?

TIA