This is where the fabricated upright and wishbone package will come into play as the parts from dead sierras or granadas are not only damn heavy they don't do much for how the car handles...

You don't need discs on the rear of a 7 as the rear won't be doing much breaking, it the balance aint right you are going to lock the arse end up every time you dab the brakes.
Drums are cheaper and maybe even lighter, you can drill holes in them if you really feel the need as ventilation but if they were good enough to stop a fat lardy Sierra they will be more than enough to cope with 7, just use quality friction material.

Too many fit daft horsepower motors yet the best thing with 7 is handling, braking not outright power as these beasts are too light to use it.

Reet best I shut up as spaceboat nicely warmed up, Im ooorf for a wee buzzabout