I however did find this site too.
http://www.lightner.net/ybdb/serno.html
Unless Im miss reading that it should be a 1955 because the first few numbers of the Starting Engine Serial No. are 1-09
Also because the starting Vin numbers for the 56 are higher than your possible number of
Starting Chassis Serial No. (VIN) 1 020 746
Yours 10035046
I hope that makes sense. Trust me I had to re-read what I typed a few times to understand what I was trying to say.