Check with both Blue Ox and Roadmasterinc.com
You probably will have to call them. A front hitch or custom built winch bumper might work well, and then install a bracket on that to 'look' like the cross bar that will come with the hitch system.
The bracket system stops at a pair of upright brackets that hold a crossbar.
The hitch includes the crossbar, and hitch that fits to it with 1" diameter pins.
What I did with my Manx dune buggy is take the crossbar to my buddy's house, and he created a bumper on the dune buggy that looked like the cross bar, and I could attach my Roadmaster hitch to the buggy bumper.
The fabricator of the 4 wheel drive system will not hesitate in taking on this sort of winch bumper or front hitch modification. Afterall they are changing a 2 WD van into a 4x4, and this is very small modification compared to that one. . .
If you are installing the whole 4x4 system just to tow it, or to take it off road sometimes? If you just want to tow the van, consider a driveshaft disconnect. Basically it will put a section in the driveline, that can split it in two, so that the van can be left in park, and the rear wheels turn freely. A simple lever will disconnect or re-connect the driveline. Check with Roadmaster for a company that builds driveline disconnects.
Good luck,
Fred.
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