putting the spindles and hubs on wont raise the height, but they allow for longer shocks that could raise the ride, with the standard spindles & hubs 400 length shocks can be used and are 1/2in longer than the yfz, just depends how high you want it
that is with 16 5/8 custom shocks with yfz spindles & hubs, about same length as 450r, but standard 450r can't be used