I rather doubt the Soviets would have been stopped at the West German border. Their army was just too large.

Gen. Sir John W. Hackett wrote a very interesting take on a NATO Soviet conflict in the mid 1880's (published just when I was leaving the Canadian military) called The Third World War: August 1985. If you see it, pick it up, it is a very illuminating read by a former NATO commander. He postulated that the Soviets would have been stopped well before they reached the Rhine.

He also noted many of the same problems the Soviet army had that the RuZZians now display.