My reference for the date for the front facing goat is non other than
Scott Thompson's "Great Northern Equipment Color Pictorial" (book 1, page 73).
Were there some cars painted in the front facing goat after 1936?
Probably. Were there very many of them surviving in 1950-51 (the
O.P.'s date of interest)? I submit "not many" as my answer.
Can he use some of them on his layout? Of course he can. The
questions are "how many?" ... and also "what service was the car in?"
and "what type of car?". And, of course, the proverbial "it's my RR
and this is what I want to be seeing". I did not answer "none".
There is no way, at least that I know of, to "know for sure" what
percentage of cars would still have the front facing goat. At the
same time - as the percentage goes up the "feel" of the early 50's
is compromised ... more weathering on those cars would
- Jim B.