Gold at least all of 1 of either I-C, I-B, or I-A.

Sell the race car. Buy Tommykaira ZZ-S with: Brakes, Full Suspension (under For Professionals), Super Soft Tires, Sports Transmission, Clutch 3, Flywheel 3, all Weight Reductions, Racing Modification, Engine Balancing. Also buy; Chip, Muffler 3, and Turbo 2, but don't equip any of them.

Do Nationals; JP 1, UK 1, IT 1, GR 1. For the first race: Settings: Spring Rate: 18.5/18.5 Ride Height: Lowest Camber: Lowest Stabilizers: 1/1 Downforce: Max To move the cursors for adjustments: L1 and Left or R1 and Right.

Do Nationals: US 1, FR 1-2, then the rest. For the US 1: Equip Turbo 2. (This is for ~246HP) For FR 2: Equip Muffler and Chip. (This is for ~295HP)

Do Pacific Seattle.

Get in RX-7 LM Race Car.

Do Euro League. For first race: Settings: Equip: Super Soft Tires Spring Rate: Highest Ride Height: Lowest Camber: 0/0 Downforce: Max

Sell the race cars. Buy Subaru Cusco Impreza.

Finish Pacific League. Settings: Repeat from RX-7.

Sell 2 race cars. Buy Toyota GT-ONE Road Car, and Turbo 4.

Do World League. Equip Super Soft Tires.

If more than 1 License was all Gold. If I-A and either I-C or I-B: Use FTO LM for Euro League with same Settings as RX-7. Sell cars for Cusco Impreza and do Pacific League.

If all 3: Sell all cars before buying ZZ-S, after Nationals, buy Cusco Impreza and do Pacific League. Get in RX-7 LM for Euro League, and sell for GT-ONE.

This is probably not optimal, since I'm not the most knowledgeable about Suspension Tuning. And the multiple Golds may not be either, but there isn't much to do with the extra credits, seeing as though the Escudo isn't in the budget.