Kc;
Late bolt circle of the 1800E (5 X 4.25 = 5 X 108 mm) has fewer wheel options than the earlier (different!) bolt circle, and in order to not change gearing or result in Speedometer error, you should maintain Overall Diameter (Circumference) of whatever tire you install, to the original.
See Tire Dimension Chart here, under Reference Info:
http://www.sw-em.com/Wheels_Tires_Su...otes.htm#Tires
Others can help with Offset Info which is also quite important.
Cheers