Thanks Chris! You've pushed me over the edge, no going back now...
I bit the bullet and eased the rubber casing back, thank god for cheap Chinese glue that snaps apart! I've found the screws on both sides, they're both covered in glue but still turn easily.
I'll wait until tomorrow/daylight to go any further.
I've found what seems to be a
decent tutorial on collimating binoculars, so will do a bit of reading and twiddling in the morning.