Van/Truck Below Eye Line Mirrors-Interchangable?

[Ironhorse]

Curious about this. Have what I think are the below the eye line mirrors for a van but not sure. Will post pics later today of what I have. Would the van mirrors mount to the door the same on trucks or vans?

Also, what is the proper sequence for assembly using the steel washers and the nylon spacer washers so the mirror arm and the mirror head will swing and pivot up and down as needed. What I have came in a box completely dis-assembled, no hard ware. Was able to find steel washers and found correct nylon/plastic spacer washers but can't seem to come up with right combination of washers and spacers to properly seat the acorn nuts tight.