Sixto........

Here's the problem that I see with the 2.88:

If you attempt to use all four gears, 1-3 will be very short:

10.6
6.9
4.1

The current vehicle has ratios 2-4 of:

8.3
5.0
3.5


I do not believe that you want ratios that are that short around town. The current setup is relatively short and it shifts very quickly.

If you use the 2.88 and keep second gear start, the vehicle will be slow as hell on launch.