I second Skycrafts post. Why not consider it? I started a thread "rear coil over conversion" and it looks like Skykcraft, Ronkahn have found all the parts you'd need from Summit and Outcast. Rgbray1 started a thread "Kirk...we are under attack" that has his conversion journey. I don't know if the Foxbody lower coil mounts would work on the rear you have, nor if a fox 8.8 is available where you are, but there's tons of examples of 9" rear coil brackets guys have made with plans available on here. MaSnaka has some great pics of the ones he had made up.
Here's my parts list
QA1's QA1-DS602 $343/pair
https://www.summitracing.com/parts/QA1-DS602
Coils QA1-14HT250B $107/pair
https://www.summitracing.com/parts/QA1-14HT250B
Lower mounts LMR MM-MMSM2 $66/pair
https://lmr.com/item/MM-MMSM2/79-04-...hock-Mount-Kit
Upper mounts Outcast Autoworks $70/pair
https://www.outcastautoworks.com/col...31206264242227
I'm planning on starting my install right away, but it's essentially the same as Skycraft and Ronkahn.
While your in there, you could upgrade to the upper control arms of your choice and replace bushings/bearings for a few hundred bucks.
As for the front end, maybe take the opportunity to do the same