I have this Holdsworth frame that I got repainted and am rebuilding with mostly modern parts - I recently realised that I'm not quite sure how to run the derailleur cables past the bottom bracket.
I have seen bikes from this era with brazed on above-BB cable guides, but this frame doesn't have them.
I then remembered my Btwin has a plastic under-BB guide, so I got one of those but realised the hole in the Holdsworth's BB cage looks too small to have any sort of screw in it, and looks more like a drainage hole.
(Also, even though the guide says "screw on type", it looks quite different from the screw on one on my Btwin, which has a split plastic nub which wedges into the BB cage hole when the screw is tightened. I'm really not sure how this one I got is supposed to be fastened - I looked up some diagrams on Shimano's site but they didn't help)
Does anyone have any advice on how I should go about guiding the gear cables? Thank you!