I have done this before. The way I did it is with a sprite for the needle. Then I plugged in a formula:
every tick | set angle to 185/700*Player.Car.Speed + 45. (my needle sprite is pointed straight down, so using this formula, at 0 speed, the needle points 45 degrees past straight down which is bottom left, and at 700 (my car's max speed) it points 230 degrees (185/700*700 + 45 = 230) past straight down which is top right.
My capx is too big to upload to the forum, but if you need to see it, I'll try to shrink it or put it on google drive or something. Just let me know.
EDIT: Wasn't too hard to shrink. Just check out the every tick event and the needle sprite.
(W for gas, S for brake)