Front Suspension Upgrade
granada with metric calipers is probably the most popular and least expensive choice. after that it's mild to wild in the aftermarket segment. watch carefully because a lot of those are 4.75" bolt (or metric equivalent).
ultimately it's going to come down to what wheels your want to run in that the rotor/brake setups favor larger diameter rims, so keep that in mind as well.
what coil over set up are you going with?