I picked up an Expert too this week, all 105, 6 speed indexed. Looking at it in more detail last night, the rear wheel needs serious work so I have a set of GP4 wheels with Dura-Ace 8 speed hubs that I am considering swapping in. If I can find a Uniglide compatible cassette is this a good idea? Can I make the 105 RD and shifters work or does more need to be done? I'm new to drive changes.