“He ain’t fit to tote guts to a bear” is a disparagement of a cowboy cook. The origin of the phrase is uncertain.
 
 
3 October 1956, Burlington (NC) Daily Times-News, pg. 7:
One Florida soldier wrote: “Our officers are not fit to tote guts to a bear.”
   
16 July 192, Valley Morning Star (Harlingen, TX), pg. C6:
Sunday breakfast prepared by the survivors among the apprentices. It should be noted that those malcontents in our chapter who have said that our caterer is not fit to tote guts to a bear are unnecessarily unkind.

30 September 1976, Chicago Tribune, “The great chili debate” by Carol Rasmussen, pg. D1:
As for the cook who makes chili without beans, (H. Allen—ed.) Smith snorts that it reminds him of an old Texas saying about any range cook whose grub was consistently miserable—“He ain’t fit to tote guts to a bear.”