I'm surprised you didn't mention Randy Kobes' excellent PPM::Make module
Sorry, I meant to reply to this earlier - got waylaid :-)
I don't follow the relevance of this wrt this particular meditation/tutorial. We all know that randyk does only work of the highest quality (not to mention the admirable character of the man), but I think a treatise on PPM::Make would be more appropriate in a meditation regarding the building of PPM distro's. When it comes to building and installing modules, I think the relevance of PPM::Make is somewhat tenuous (to say the least) - which is the reason that I haven't mentioned it. (And I do want to keep it simple.)
I think I see where you're coming from, btw - doing it that way means that PPM keeps track of everything that's installed.
(Great sig !! - I work in the dairy industry :-)