Ford 8.8 in a Nova?

[Knaller]

Hi guys! Im new to this forum and looking for some rearend suggestions.
I am currently in the build of a 71 Nova. Not exactly what You are building over there . Due to requirements to register it as a historic car i can't run too "modern" suspension parts. So here is my setup. Hotchkis 3" springs front and back, front springs are shortened 1/3 coil, G-Mod, stock A-Arms, four wheel discs, 383/700 combo. I have the 8.2 10 bolt rear in it and want to replace it with a ford 8.8. Thats the rear end i can get for a reasonable price... Living in germany didn't make getting parts easy... It's out of a mustang and has the 4-Bar links still on it. Would You change the leafs for a 4-Bar setup? Which spring rate do You recommend for this one? Car will be mostly street driven, but i do a lot of driving windy roads in the hills here....

Thanks for Your help!

Some pics of the build: