Gabby, thank you for the great clarification on the 318 QH and sharing your experience. I am on board with all of the items needed for the QH PTO set up for a snow blower or thrower. The JD Parts site is a wealth of information. I've used it a lot for researching how this QH configuration and ordering miscellaneous parts from the dealer.
The 46 snow thrower (I now remembered not to use blower here) is essentially the single stage quick hitch version of the 49. It has hydraulic chute control though unlike the model 49.
I guess in the end this all comes down to what I want to tinker with. I think I am going to give it a go as I don't like thinking about the could have, would have, should have later on. By the time I buy the QH and drive shaft, I might as well get the 46 blower to with it. I plan to have this tractor for the next 30 years as I have a number of attachments (3 PH, model 30 hydraulic tiller with extension and 3PH setup, 54 four way blade, powerflow with JRCO 18 bushel cart, front mount dethatcher). Might as well as add this to the list for now.
If all goes well, I will get some pics on here in the next week or two.