There are some very interesting manuscripts within WSU’s archives. See especially Wallace Cessna Aircraft Company Collection. They have production cards for several different models but, unfortunately, not for the C-170. Check out this brochure for the 1954 “All-Metal Cessna 170” or this advertisement for the 1953 C-170.
There is a 1938 proposal for four versions of a pursuit fighter in 1938. They were pushing for the P-1 and P-3 — the wood wing versions. They also had a proposal for a light cargo plane, the P-260.