what size early 90's cannondale

[theclarinettist]

I hope this hasn't been covered before?

My height is 172cm so which size early 90's cannondale should I be looking at? I used to ride an 18 inch 1989 sm600 but that had the sloping top tube, and I'm now looking at a level top tube model. Am I correct to assume I should be looking at the same size?

Thanks in advance

David