Regarding the Q. on the CPR 46' flat cars:
Figure 192 is a plan for a CP car with straight side sills.
The CPR built 800 46' flat cars between 1929 and 1938 starting with five-hundred CCF built 300000 through 300499 (the CPSIG website has a plan of this series built in 1929). 100 more were built in 1931 in the 300500- 300599 series. There is a photo of one of the last series of 46' cars (no. 300715) on the STMFC website which was part of the two-hundred car order built in August 1938 and numbered 300600-300799. Some cars cars of these series remained active until April 1988 having been re-numbered in 300900-300999 sereis.