Yes I know if i change the freewheel to a larger range I will need a new rear mountain bike type derailler. I have no problem spending the $ for that.

Thank you for the links to the new widerange freewheels available. I did not know of their availability. Do you know if any of them are any good? Do you know if i could use the 8 9 or 10 speed freewheels? I am not familiar with new 8 9 or 10 speed freewheels, I assume if i used 9 or 10 i would need a front cranksest that is designed to work with modern 9 or 10 speed chains? That might not be a problem since i may use a modern crankset anyway.

What are these new 8 9 and 10 speed freewheels designed for? Are they designed to use on vintage bikes but to get more speeds and use modern cranksets? Or are they designed for electric bikes that have wider hubs than vintage bikes?

I am assuming if i got one of these new 8 or 9 or 10 speed freewheels to use on my Trek 760 I might have a problem with fit on the rear hub, it may not be wide enough. But I am guessing. I know that
the Suntour 7 speeds used cogs that were thinner to fit in the regular 6 speed freewheel space width.

I doubt that these new 8 9 and 10 freewheels are thinner to fit in the regular 6 freewheel space am I wrong?

My trek 760 has a 7 speed suntour freewheel.