BOOYAA! I made a video, it`s fairly rough but it gets the major points across for the difference between this gun and the TM style AKs.
Once in the gearbox I only found that the anti reversal latch was super different with the little return spring going into a hole in the back of the latch. Besides that everything else is fairly obvious.
APS AKS-74U EBB disassembly takedown - YouTube