been through all this myself if the steering wheel and dash shake then get the tracking and balancing checked first its free in most garages Kwikfit etc...
Check Steering
rock the wheel left to right any play where the wheels dont react is bad and the rack is on its way out.
Engine mounts
you need a 2nd person put the car in reverse and then 1st and lift the clutch with the engine running and handbrake on. watch the engine move back and forward if the engine dips or lifts more than 2inchs change the mounts normally its the front one that goes first and it will dip like 2inchs and lift about 4inchs and is very common think most people here have chnaged theres at one time or other. ***if you change the mounts yourself examine the bracket on the front of the engine as i changed mine in jan and the mounting bracket was fatigued and snapped about a week later***