I picked up an '86 gray Prelude for $50 too, and it's in a lot worse shape than yours. So, you did well. You can go with a new rim and rebuild the wheel as one option. My Prelude came with 700C wheels. Should be no problem swapping wheels.
The Prelude is best described as a sport tourer, based on the frame angles and wheelbase. It's lighter and livelier than the 'tour' spec bikes. The Columbus tubing is lighter than the LeTour's straight gauge tubing. I don't see why you can't put the Lemond's drivetrain on it for now.
Mine requires major refurbing, but when I get to it, it'll get Superbe Pro gear, lightweight wheels, as an upgrade. I want to see how well this frameset rides with higher quality components. I have an older but similar Japanese-made Champion #2 tubed sport tourer to compare the Prelude with.