you will need a power steering pump pulley remover(available for purchase or rent at most major parts stores) as it is pressed on in order to remove the pulley to access the pump to bracket mounting bolts:
See Figures 1 through 5
Fig. Fig. 1: Removing the steering pump pulley
Fig. Fig. 2: Installing the power steering pump pulley
Fig. Fig. 4: Location of the power steering pump pulley - 5.7L engine
Once you remove the pulley you can access the pump to bracket bolts and remove them. the pump can then be removed from the van separately.