Be attentive when reassembling if your unit doesn’t have a tape, which keeps antenna interconnect cable in place — I’ve accidentally got it squeezed with back cover.
Just FYI, for whatever reason my brand new OnePlus 5 had 0,8 mm stars screws instead of T2 Torx.
I agree that it would be better to overlay red the two vertical cables. Other than that, this step is rather time consuming, than complicated. Obviously you should be attentive to not damage the cables, but if you put moderate force during 3-4 minutes, the battery will finally separate from the case.
Wondering if it’s safe to use hair dryer at this step.