Hello My suggestion would be, if speedometer in first person view would turn all the way around and would'nt stop at the maximum vehicle speed, and it would be nice to see the same for revs, that it would go over the red line.
that would be somewhat unrealistic if i am understanding you correctly, BeamNG Devs try to make the game as realistic as possible.
why would it be unrealistic like for example on older cars (if tuned) the needle of speedometer goes pass the speedometer limit and continues to spin around, same for revs for example on supra or civic with vtech revs go past the redline
Because most cars with analog speedometers have a stop just after the maximum speed shown on the speedometer, they stop it from turning any more so any person who tries to go over it cannot see what speed they are doing; for example Malaise era cars (70s-80s), during the oil crises they lowered maximum speed limits to 55mph so most speedometers stopped at 80-90mph even though some vehicles could go quite a lot faster, thus encouraging staying at safer and more efficient speeds.