Upgrading Bar end shifters

harpo Posts: 173
edited November 2009 in Workshop
How easy is it to replace bar end shifters on a older touring bike with up to date 105 brakes/shifters? If I do change them do I need special ones for the V Brakes?

Also if i upgrade the deraileur can I change the cassette over to a 9 speed from a 7 or 8 speed one? Will there be enough space in the drop out or is it likely to be too small?

Lastly has anyone seen a decent touring bike groupset anywhere for sale?