My thoughts exactly Mark , Didnt want to be the odd one out an say something , thought i wasnt seeing something that others were to be honest,
Aom if i was to use a jacktie i would run ledger thru jackties , then maybe use a 3ft butt as a type of raker .
i would sit bottom of butt on top of a sidewall fixing connect it to ledger using a double slightly pushing ledger up with thumb as i tightened double so as to keep pressure onto the sidewall fixing, then possibly another small butt off ledger into the sidewall itself so as to gently keep pressure on the raker butt to keep it in place similar to the picture in the website.
hope you understand what i mean as having trouble explaining, possibly cos i only been out of bed 20 mins :laugh: but this would help keep pressure off the hilti ties to stop them bending.
I also have another idea i used in past but i got no picture to show you but basically you need a rectangle piece of flat metal say approx 12 inch by 24 in 3 quarters of way up get a 6 inch butt welded in the middle of it and 2 drill holes preferably slot type for adjusting to different profiles , then unscrew couple wall tie fixings , screw plate to purlins using heavy duty type screws/ self tapping bolts , then because you have your butt 3 quarters way up plate the bottom of plate acts as a pressure plate against the wall.
also look at the brackets they sometimes use to hold small units up on walls its like an upside down letter L they usually use 2 or 3 of them to stand air con units or water type tanks on them up a height , try getting someone to fabricate something similar for you.
also in the concrete engineering industry they use threaded tie bars to hold superslims in place when doing formwork, they sometimes put a 6 inch butt over it before tighting so they can punch up for handrails :toung::nuts::laugh::
long post for 20 min awake time need a snooze now