Santana Titanium from the 90's
I'm considering buying a used Santana Titanium frame tandem. I think it was built late 90's. It currently has Shimano 105 3X up front. If I bought it as an entry in with a plan to upgrade to current components will I run into frame compatibility issues? The biggest thing i'm sure is that there won't be disc brake compatability.
The main reason for this is to get my wife interested in riding with me. We have a 'cruiser' style tandem that's fun to ride sometimes but it doesn't fit the bill for a long weekend ride.