Twelve years ago I wrote a bit about Pynchon’s use of eye dialect in his underappreciated 2013 novel Bleeding Edge. In that book, the dialogue of Californian woman (Vyrna McElmo) is stylized so that her -ings are spelled -een, presumably denoting [in]; e.g., “I’m still, like, vibrateen“. I am now working through Vineland (1990). In that book, another Californian, DEA agent Hector Zuñiga’s dialogue features a different eye dialect take on the same variable: they are spelled -ín, presumably denoting something similar, as in the following passage (p. 28):
All of you are still children inside, livín your real life back then. Still waitín for that magic payoff. […] Rill puzzlín.
I wonder if there’s a prosodic difference between (Caucasian) McElmo and (Latino) Zuñiga’s renditions of -ing in Pynchon’s mind, though.