Whart- I hope you enjoy the Guzzi. Sounds like you really are a 'serial collector'. I'm a cereal collector, and I have like 4 boxes in my cupboard right now. Na, really, I'm the type that can't get rid of anything- I still have my first Guzzi that I bought 20+ years ago. It's in pieces, but I still have it.
let's see
handlebar risers- you can go with risers or install handlebars. There are several companies that market risers- look at MPH, Williamsville, etc. There's a thread just started on this subject here.
Pipies- there's Guzzi Ti pipes that come with their own new 'race' computer. Supposedly sound and perform well. There's Mistrals, Leo Vince, Staintune, and Neptune. I have Mistrals + a Stucchi crossover and I like the combo very much. The crossover is as important as the pipes IMO.
Chip sets- no such thing. There's a PowerCommander (PCIII) that is sold by Todd Eagan aka RacerX on this board. Many swear by it, but I have no experience.
Tires- I think I read someone (Mike? Paul?) has recently been lauding the Diabo or Diablo Corsa as a fabulous tire. I'm not that good of a rider and there's lots of flat parts here in the midwest, so I have Metzler somethingorothers that hold air and roll- my two biggest qualifications for tires. They stick ok as well.
Aftermarket suppliers (not complete by any means)
MGCycle
MotoGuzziClassics
MPH cycles in Houston is excellent
Ned's Auto and Cycle here in I-o-way is also a great dealer
Closer to home for you is Eish Enterprises
Agostini's in Italy
Several other Italian companies advertise on this website.
Tex, please DONT, DONT, DONT post 'The picture'. No. Dont. It hurts me.