Stiff shifter on automatic transmission

I just received a 92 Ford Aerostar (it was free). When I try to shift it into gear, it is very tough to move shifter. It is an automatic transmission. Once the car is warmed up, it is still hard to shift, but not as badly as when it is cold. Also, cold temps make the problem worse. Once it warms up, it drives well. No problems while driving either, just putting into gear. Any thoughts?

Crawl under the van and check to see that the tranny mounts on the cross support are intact. If the tranny/engine are allowed to move, it can cause the shift linkage to bind, making it hard to shift.

Tester