At the very least the 97 Van PCM (DPC-315) would require rewiring the DPC-203 PCM connector to match. You may be the first to try this so don't expect much help. Reflash tuning may have problems also.
Federal DPC-203 PCMs that should work as plug and play per PHP's PCM chart:
AUG-0 through AUG-6, p/n F6TF-12A650-ATA through ATH
BEG-5 through BEG-8, p/n F5TF-12A650-FF through FJ (may not be correct p/n)
MLE-0 and MLE-1, p/n p/n F7TF-12A650-SA and SB
SOD-1 through SOD-5, p/n F5TF-12A650-BTB through BTF