The answer to your question is yes a World Voyageur with original parts (39/52, a Crane GS, and Suntour bar end shifters) will shift a 12-25 ten speed cassett and will most likley go eleven. 13 to 34 7 speed is a not a problem I dont have a 10 speed that large but i don't see why it would not work. As a W.V. is 126 mm from the factory I would just put the wheel in to test, it if sanafactory then spread the frame, no need to do anything with brake bridge. Things to be aware of , you may need to adda 1/2 or 1 mm washer to the drive side axel, its tight. A 114 link chain will work with 52/34 but your mechanic might want to add a link or two. Good luck on your project World Voyageurs are great bikes