If mounting 2 of them - mount them inline with the hydraulic cylinders.
Try not to pull on ONE hook at a time - for example, you need to pull something heavy across the ground and you attach to one hook - do not!
make it so both are being used. If single is used, good chance of bending or stressing metal on that one side.
The gap you are referring to - that is just an exploded view showing how they go around the bucket.
ALSO - on that bucket the lip is much thicker - there is space behind that lip - but that will not be a good place to use those hooks - you will need to bolt on the lip to be effective.
This is the bolt info on those hook sets - 1/2" x 1-1/2" Grade 10.9 Bolts
I would use grade 8 bolts not the ones mentioned.
EDIT - those bolts in the picture USED on that particular bucket are not the ones that come with the kit - those bolts had to be at least twice as long to get through the thickness of THAT bucket area. (Kit says 1.5" bolts - those are much longer! )
View attachment 124637