Historical clue formulations

• See 66-Across — 2026-03-05
• "If wishes were ___, beggars would ride" — 2023-07-17
• Mustangs, e.g. — 2009-06-29
• Engine capability, slangily — 2007-02-18
• Motor's power, informally — 2003-05-07
• Derby participants — 1999-09-20
• Derby entries — 1996-07-23
• Engine power, informally — 1995-01-29