WIRING LOOM CONNECTORS

I'd like to refurbish several plastic wiring loom connectors to bring them back to a decent finish and wonder if anyone has managed to do this with any degree of success using modern cleaning jollop like Muck Off etc.Bearing in mind they are 40 years old and the plastic becomes discoloured and deteriorates with age I'm not expecting to get a showroom finish.Maybe an overnight soaking in Gunk or similar might do the trick but thought I'd ask around first.

OK it's confession time - it's not for an ST - it's for the Honda SL125 Trail bike I'm having a go at
but the same task applies to any old Jap bike!
Brian

The connectors are still being made (Japanese MOLEX copy or something) I just bought new connectors from Digikey or Mouser and replaces the plastic housing. Still have the blade contacts in my parts box someplace..... If I remember where I got them for sure I'll let you know....