Only thing i'm not able to cheat is to get the mx-5, the box stays grey. So i have to complete the special event.
Edit: now the mx-5 is mine. ? ? ? , so i confirm the car hack still works too. Credits to foreverspb for the initial hack, and for teaching us where and how to search the values.
A little note - it seems in 2.9.1 there's some kind of double check built in. The values you get before the circle completely stopped drawing are useless to edit, you MUST wait until the circle has stopped and the game is loaded to 98%, the short moment before the "connecting to server" message pops up. In this moment the "interesting" values are duplicated to another ( lower ) adresses. Please use your brain a bit, experiment, and compare what happens BEFORE and AFTER the circle has completely stopped.