Forg Were liveries of that style used as far back as 142's?
No, they weren't. But then 16V DOHC engines weren't fitted to 142s either, so....
The factory 140 GT-kit body stripe kit was different, as seen below.

That profile picture started life as a 1986 Group A drawing, but the front end and and boot lines were changed to make it into a 73 model. The external shape of the cabin area didn't change from 140 to 240..... but the body's front end in front of the front wheels is shorter.
Busy times are ahead. Getting the local sign writer to make the Swedish war stripes from adhesive vinyl is one of the simpler jobs.