>In terms of putting the quad light grille on an 86-91 vanagon, what lights
>are actually usuable? Someone said something about raiding an early
>vanagon for its round lights, but that will only give me the round light
>and its mounting/adjusting hardware, no? What about the two high beams
>or those included in the grille? Will the round lamp mounting frame bolt
>right onto my 87 vanagon or do I have to rig it?

I don't know how I can make it any simpler.

the quad round headlight / driving light grille is just that, - round.

that's why you need the metal headlight buckets off an '85 down Van, if yours is
'86-'91. 

The '80-'85 US single round headlights are dual Hi / Lo beam. 

the smaller driving light buckets are integrated into the plastic SA grille. 
 
All '80-'91 grilles mount with basically the same tabs. 

chris