I popped into a hardware store (nice big old one) and got some brass 4/40 fixings, quite long will be long enough.
I also have some 4/40 lock nuts on the way thanks to the bay.
This should fix both models, and leave me with spares
I'll also dremel up the rear shock mount and any spares I need will now be 4.1 parts.
I think this is solved! Thanks all :P
edit: did not of course need the brass bits!