Id try A air gun . use low pressure to start work you way up. next Id use a 3 loop system on the Velcro leave a longer piece of wire to feed thru the slots,you see I hve a large variety of aircraft safety wire its stainless has many different sizes from small straight pin size to .035
This can not be all this hard.. are the strap holders formed into chassis? I've put and replaced straps on a few
on the ones I have done the strap mounting brackets where held down with screws thru bottom of chassis .on another I had to work strap thru slot sure it took some time but was...