I run 8.5" rustys. Ford coils are bigger diameter and be a still ride. Won't fit in buckets either. Don't recommend them.
Biggest thing done forget is coil retainers so they don't pop out on flex. π I have seen this happen a few times. Good spring rate gives better ride quality like a progressive spring. Aim for most lift from spring vs spacers. Adjustable coil spacers are nice to fine tune before and after extra load or engines swaps.