Here's how to fit them without all that fuss:
formatting link
the '2 fingers' bit isn't easy to photograph as my right arm's in the way of a good camera angle, although I'm gripping the bolt with the first knuckle on my first 2 fingers; basically from the 'back' [interior] the 2 fingers are for holding in place, while the bolt is screwed on from the 'front' [back of the vehicle]
'innercentralback' is the innermost of the 4 bolts, the spanner there risks dropping off, needing a bit of recovery work with a screwdriver; the one I didn't completely undo for my purposes would be the 2nd-innermost of the 4, although as I say it's quite possible to reach it with 2 fingers, as with the spanner in 'outercentralback'. All the actual turning is from the clear side.
At innersideback/outersideback, fingers go in just as spanners do.
HTH
Regards
Mark