Oh I can't remember those metal rails. Good call, and as Per mentioned it's like that gravity spring feed tube.
Deoxit is wonderful stuff but it is so expensive I usually don't use on switches. I do use on the Williams horseshoe drops however.
But it leaves an oily flim that doesn't evaporate so I my mind it's just going to attract more solenoid dust and get crappy quicker.
I just use qtips, strips of business card and IPA.
Soak a 1/4 " piece of card in IPA for a couple seconds insert between contacts press together lightly and pull the card out. Qtips dry after to buff the contact and or wet to clean the whole length of the blade.
Deoxit is really good for things like the mating connectors with the round molex pins. And I actually ran a test on a couple funky lamp sockets. Ohm meter hooked up and reading high K ohms sprayed some D5 and actually watch ohm reading fall fairly quickly down to a low ohms reading of single digits. So yeah good stuff.
Glad to here another BH back in action.
It's so weird it's been so long ago that I picked my 100% dead BH project up and it is still my favorite game, and having very few issues.