I think I have the IH 377 subframe. It came with the 1811 I recently purchased. I have used the blade on the 1811.
I was able to mount it onto my 1864 this weekend, but the lift rod was too short and the lift arm on my 1864 is different than the one on the 1811 so they would not be compatible at this point.
Check out the pics on this thread:
http://www.onlycubcadets.net/forum/s...highlight=1864
PeterJ