Ok in a astounding moment of brilliance I connected the jumper cables backwards and now the van will crank and has fuel pressure but no spark. (the battery had been dead for nearly two years...) I had jumped and ran the van several times while in storage, so I know it has no preexisting issues. I assume there is a fusible link somewhere in the harness for just such a case. Anyone know where that would be? I have already checked the under hood fuse box and none were blown, so a diagram or a pointer would be appreciated

 

Welcome to DF
What size engine to you have? And when it cranks,does it sound like you have compression?

 

it is the 3.3 V6 in excellent condition. because I have no spark I assume either I killed the PCM or blew a fuse or fusible link somewhere. I have fuel pressure and the motor cranks well, and I have swapped out the coil still no spark. because I know the battery was connected reversed I assume I indeed killed the PCM, but prior to spending that much cash I want to cover all my bases.

 

If you want to cover your basis, then you need to diagnose all the parts in the system to pinpoint the exact problem that way you don't throw unneeded parts at the problem. You should start by getting a factory service manual. This will walk you thru step-by-step instructions on how to find why no start.