Possible Clues:

• Carriage’s singular function on short trip east
• Ollie's partner, famous comedian, in one-seater carriage
• Ollie's partner, famous comedian in carriage
• Phaetons replaced single-seater carriage
• Sort of posh, neat carriage
• Horse-drawn carriage for one
• Horse-drawn carriage, second phaeton, abandoned
• A single-seat carriage with two or four wheels
• Phaetons can be turned into a light open one-seater carriage
• Light carriage