MK1
MK2;
Look carefully at the headlights, MK1 are flat and rectangular, MK2 are round, there are other ways, such as the bonnet and slam panel, and wings and grille (most prominently) are different, MK1 VTR's had a 90bhp blacktop engine, MK2'S have a silvertop (whether than be 90 for a early MK 2 or 98, and you can find the guide that show's you which is which, but basically - dipstick to the right of the heatshield - 90bhp, Dipstick in the center of the heatshield - 98bhp. They are both silvertop)
Hope that helps.