Danny Dot wrote:
If I buy an older plane that qualifies for Sport Aviation (e.g. less than
1300 lbs), but was certified "Utility", do I need any paper work to fly it
under Sport.

The plane will continue to be a "Utility" category aircraft but
qualifies to be flown by a "Sport" pilot. This is different than the
new "Sport" category of aircraft which are basically Ultralights.

-Robert