From a diagram I saw in the service manual, it is under the right side lift cylinder, such that you have to raise the bucket to see it. I just found that myself after looking at and buying one but only finding the serial number of the ROPS. I pick mine up on Monday, will double check on the...
Update: I finally got to see it yesterday (they seller has been hard to get in touch with), but I agreed to buy it for $8000 including a pallet fork attachment. I'll be picking it up Monday. It has new wheels and tires and is well maintained. Unfortunately it was blocked in so I couldn't test it...
I am going to look at a used mid-1990's Mustang 940 for sale (asking $8500). Are these overall good machines and relatively easy to work on? Are the parts still available? What should I look for specifically when checking out a used unit? I am mechanically inclined but fairly new to skid steers...