Forget the S805 device, it was never supported by OE/LE in the past and modern kernel support is making positive but glacial progress and is a long way from being easily usable. The S905 box might be somewhat useable; the choice is CE which should offer best support, or you accept the very "work in progress" state of modern kernel support in LE images.
NB: Users are obsessed with running from internal storage but this complicates the bejesus out of testing images which may or may not work and provides only marginal performance benefit. You'll need to restore the correct vendor u-boot to make further progress. There are a very limited number of people supporting Amlogic hardware in these forums and I have subzero interest in install2internal issues; that script is a complete waste of personal time.