Where is the fues box inside the van?

I can show you where the fuse box is, it's on the end/side of the dash, passenger side. But if the blower works, I really think the trouble is somewhere else, maybe the heater core not getting fed with hot coolant or is clogged

I drew a blue circle inside black circle, that is what allows (or not) coolant in to heater core, click for full screen..it's vacuum operated