Did the fleet of Swift reefers operate on Southern Pacific tracks?
"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."
This fellow has some good tips on modeling the SP:
http://modelingthesp.blogspot.com/search?q=swift
You may have to dig for the exact information you seek but the photos and modeling tips are very well done. (I like the coverage on Helium cars).
Good Luck, Ed
doublereefed Did the fleet of Swift reefers operate on Southern Pacific tracks?