Converting from 7-speed to 10-speed rear wheel My Bridgestone MB-5 currently has a 7-speed rear wheel. I'd like to convert it to a 10-speed. Is this possible? Is it practical?
You may be interested in this .. The 1992 Bridgestone catalogue (8meg PDF) 

The bike is the lower end of the range (MB-6 being lowest), meaning its not worth that much and never started out as a great bike. As its steel (one redeeming feature), its possible to cold form the frame to widen the rear drop outs to take a 10speed, so technically its possible...... 

Practically its not worth it. The bike is old and low end. To upgrade to 10Speed you would need 


Complete Wheel (at least a new Hub and cassette) 
Dérailleur 
Shifters
Chain rings


Probably 


Shifter Cables 
Chain