yep eIII's strap is about 5-6mm shorter between holes.
(never could find this sparepart when I broke one of mine yrs ago.
Couldn't use a TB02 strap as its too long so I had to
get one custom-cut as a replacement.)
eIV uses TB02 strap, as does TA05.
Just tried TA05's CF strap and it fits eIV, does not fit eIII.
To use ladders in e5 gotta do some surgery to the stickpack cradle yea?
Cradle's mount holes are different to the similar part in eIII/eIV so
can't just borrow the eIII's non-cradle mounts onto the e5.