Controll project

My company curretly has a project where I got stuck with the workload. We basically have to make a car seem it is driven. A week ago I had no idea about all these wonderful controll boards but after much research Arduino seems to be better than any other board (at much lower price)

First I have to controll the speedometer gauge and tach gauge. The PWM should be able to do that.

Second I have to move the steering wheel. Here is where I need lots of help. I want to use a stepper motor atached to the cut off steering shaft of the car. Could someone recomend me a powerfull stepper motor(something that will move the steering wheel with someone’s hand on it) that can be controlled with Arduino?

Considering I have to make the car seem like it is driven for two minutes, the 16K Arduino provides is really small. I have to controll the steering wheel, speedo/tach gauges, and other things at lest every second. Because of that I will probablly use Firmata and keep the programming on a laptop. Should there be any issues with that?