Question: Where does the phrase "hate your guts" (for example "I hate your guts") come from?

I've heard the phrase used as a way to convey extreme and deep dislike of another individual. However, it seems strange to have just been born arbitrarily and I suspect there is a source.

Answer: 
I have no background in languages; but thought I'd add my two cents. Use of the word "guts" to describe feelings that are go to our core is clear. Aside from location and disgusting visual appearance, there may be also be an association with the abdominal gripping sensation our bodies feel when our nervous system kicks in.
I would venture this: When we hate someone, we hate them through and through . . . that is, their heart, their soul, their mind. If we HATE THEIR GUTS, it is to go a major step further, that is, hating the basest/vilest part of the individual, which thus takes the hatred to the most loathsome degree.