Welcome to the club! I'd say my closest comparison is converting a late 90s Lemond Buenos Aires to 650B x 38mm tires. It took some dimpling of the chainstays, but it converted a lightweight go-fast bike into a cushy, light-weight go-fast bike. I've actually also used it for the extremely hilly D2R2 in western MA as the short wheel base and light weight makes for excellent climbing abilities.
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