Got it. You can still Geo-Locate models with terrain and aerial imagery if you have upgraded to SU2018. If not you can try other open sources for terrain data. Depends on your level of accuracy needed.
I like CadMapper. It’s free and pulls info from Open Street Maps. See screenshots below. Once you download your area, just grab a Google Earth Screenshot and scale and align manually. Then paint your terrain with the aerial as a texture. Bonus is you get buildings and roads too (where available).
