I have used "jumper" from a PC motherboard - it fits almost perfectly and is removable.
I received my used SL1200 in pretty bad shape, and I did the mod before I had the chance to seriously listen to the deck so I had no "before and after" comparison. I don't expect this mod to do anything to the sound quality, but you never really know - member of the TimeStep forum JuanPabloCuervo measured the pitch stability of his Sl1200, and found out that Technics had a bit better pitch stability when the stylus illumination light was on. And he also found out that when he replaced the incandescent light of the SL1200 for the LED diodes of the later models, this "positive effect" was lost, so the pitch was worse with the LED on...