As Andrew Shadow pointed out in
this post in another thread some of us have used FyreFly switchbacks with clear lenses. But I'm not aware of a kit except for UK users. It included a new socket (like out STs) because they don't have the running lights other STs have.
It really helps to include a link to what you're talking about. Your spelling of 'fireflies' could mean a different product or you just spelled the name differently.
As a kit goes you may be thinking of the included resistors in heat sinks. Don't use those. Instead get an
LED compatible flasher/relay. It will do the job of wiring on one resistor for each turn signal. It's plug n play unlike wiring those resistors.
It's my opinion that there's maybe one manufacturer in China making the clear turn signal lenses for the ST1300 all years. I went to ebay looking for the cheapest prices with the highest seller rating. I paid about $25 shipping included.
If you go that route you'll need to clean up the flashing (plating) in the socket with a small file or sharp knife. There's a ton of info here if you search 'switchbacks'.
