Mambo143,
Welcome to the forum. Glad to have you here as a member.
Your 446 is a "garden tractor". The 48" blower you currently have is designed to fit onto the two garden tractor series made by Case and then by Ingersoll.
The blower in that listing is very similar in design to the blower you have but that one is set up for use on the "lawn tractors" that Case and Ingersoll made. There is no question in my mind that it will not fit your tractor nor will it fit any other Case or Ingersoll garden tractor.
You can use a 38" blower that was designed for the 200 series of garden tractors if you find one and then add the wings so that you won't be driving over fresh snow as you blow snow. You are looking for an H, J, K, L, M, N, P, R or S80 if you want a 38" or the same pre-fix letters but followed by 84, if you want another 48" blower like the one you currently have.
What will NOT work is an SB38 or SB48 model blower because those are for the 4 digit Ingersoll models with the engine reversed in the frame.