I just picked up this Fisher Montare (T6G Ser.#) and the FD needs adjustment. The bottom bracket guides are stock. I don't like how the cable rides against the bottom bracket, metal to metal, and cuts into the paint/metal.

Can anything be done for this or a dab of grease as regular maintenance?

grease there will collect dirt and cause more wear... see if the holes are big enough to fit V-Brake Noodle Tube Liners in there! I've used them on old canti-brake bikes to line the rear guide on the Seat tube....and several other similar situations.

One could clean up, prep and paint touch up the now bare spots. Then, as maddog34 mentioned, use a cable housing or noodle liner that fits within the guides. Do know that depending on conditions these anti friction liners tend to be of limited lifespan.

If you do decide to touch up the paint consider how much opening the guide have to accept a liner over cable. If there's any burrs or filler closing up the openings now would be the time to deal with that.

I have run my gear cables bare against many of the frames I have built since the 1970s. Only the times I neglected their maintenance for too long (cleaning mostly) have I had issues with gear shifting. But I don't ride in salty conditions these days like I did when younger so don't think much about this on my current bikes. Andy

Right. This is Day 1 since I brought it home. Needs tires too

I see now.....

A Mt Tam

Exactly.

I use the housing ling also, but mine were smaller holes so I had to get Jagwire shift cable lining with is even smaller than the brake version. If a bare shift cable could wear through a bottom bracket, then surely it would eat through those plastic liners. It doesn't. If you want "something" to spray on the rustiness, that Fluid film stuff seems to stop rust just fine. I use it on my snowblower that's loaded with heavy rust.