Alright, decisions decisions and profanity at the work bench. I owned a 4300 a few years back and had taken some good pictures of the final section and shared on cbt but that's all gone now.... I looked through my photo's and only came up with this one so maybe it'll help if you even need it. I couldn't find a schematic for the 4300 either. Not that you need any help but my own thinking here. Anyway here you go, I thought it was a mosfet driving a generic 2290 but to my surprise it's a 2166.... hmmmm.