Super License and Event Synthesizer race:

Get all licenses (A, B, Intl. A-C) to unlock the "Super License" option at the License Test menu. This will also unlock "Event Synthesizer" race in the GT
League.

Skip license exams:

Load a memory card containing Gran Turismo license data. Gran Turismo licenses (B Class, A Class and International-A) will fulfill similarly named license requirements in Gran Turismo 2.

Ending Credits:

Win all 21 courses in Arcade mode under Professional difficulty, or win all GT League races.

Easy Money:

First make 100,000cr and buy the Ford RS2000 rally car and race it in the 80's car cup. If you come in first you get ten grand and a new racing car (Nissan Skyline) which is 125,000cr!

Slightly Easy Money:

Go to the GT races and win all six of the Pacific and Atlantic races. You will get money for beating the races of course, but you also get a car worth 125,000, provided that you get 1st place in all of them. That adds up to a lot of money, you do the math. Well, I did it anyways; it adds up to $750,000.00! It is not a lot, but it is enough.