I'm putting together a bike. I'm using a 7-speed thread-on casette and a shimano 105 deraileur. I don't know what year the deraileur was from, I'd guess mid-90's
What kind of shifters can I use to get the proper indexing for the back casette? I'd like to go with Shimano STI levers if possible. Would it be possible to make a new pair of Sora 8-spd shifters work?