Background: I'm writing a master's thesis with APA citations.

In one paragraph, I cite two unrelated pieces of information that happen to come from different chapters of the same textbook. It's obvious from the chapter titles where in the book the second piece of information is located, but it's not obvious where the first piece is located. For the reader's sake, I'd like to be able to write something like:

Here's what I'm doing. Here's an interesting fact (Trout, chapter 2, 1946) and this is what it implies in the context of my research. I then fit this interesting model, described by e.g. Trout, chapter 8 (1946).

References: Trout, Kilgore. (1946). Ice-9 and its Applications. Ilium, NY: Slaughterhouse Press.

I've never seen this done before and I couldn't find anything like it in the Purdue OWL APA style guide. Another idea would be to cite each chapter separately, as in:

Here's what I'm doing. Here's an interesting fact (Trout, 1946a) and this is what it implies in the context of my research. I then fit this interesting model, described by e.g. Trout (1946b).

References: Trout, Kilgore. (1946a). Why ice is nice. In Ice-9 and its Applications. Ilium, NY: Slaughterhouse Press. Trout, Kilgore. (1946b). Containment methods. In Ice-9 and its Applications. Ilium, NY: Slaughterhouse Press.

How should I cite this? Is there an established convention for this? Am I worrying too much?