Jose,
The reference is that in 1982, the IH Corporation sold off the Cub Cadet Division to the MTD corporation (the same ones that make Yard Machines, Yard Man, the stuff you get a Wally-World or the big box "hardware" stores). The 1811 is a CCC (Cub Cadet Corporation, a wholy owned subsidary of the MTD Corporation) produced this model. Instead of having the IH "man on a tractor" logo on the grill and below the seat, it should have an Interlocking CCC logo. Take a look at a manual you have for it, it should be on there. It is a close cousin to the IH Red "82 Series" Cub Cadets and draw a number of parts that are of IH design, however this is not an IH Cub Cadet as you would think, it is a few years too new for that.
However, you have a very nice looking machine and it should have most of the capabilities of an IH CC. One thing that I like, even thought it is not original, is the black accent stripe outlining the bulge on the side panels, kinda sets them off. The original color would have been all white.