I am not a Moline person except I liked the looks of the older tractors. I did have a single block U for a time and I know it had a low seat position. Question is were all the Z series low seat models or was there a certain time that some were a higher seat position like the ZB had or was it a conversion kit to raise the seat? On the R were they all low seat or did some have the high seat and on the R I have seen some with 15 inch front wheels and others with 16 inch front wheels. Years made of same basic model or different models or years? At show sat there was a ZA with a high seat position that looked way more comfortable than the low seat like my U had and if my U would of had that seating position I might have kept it instead of trading it off. And tractor data doesn't help me any. Next door neighbor had a U that just seeing it being used if what made me buy that U that turned out to have too many major problems the reason I got rid of it. The drawbar was so high could not hook the baler up and could find no way to lower it. Tractor left in the late 60's so cannot look at it to see if I could find a way to change drawbar settings, Retired now for several years and I will turn 80 this next week. Just some things that was wondering about over the years.