Good on you. It'll always be worth more than another van done the same but that was originally a column shift 6cyl base model as it is, after all, a Sandman. I'd just go simple on it. Buy a complete rusty or unfinished project and use the V8, diff, gearbox etc in it. Something like this and sell off the bits not needed:

http://www.ebay.com.au/itm/WB-1-tonn...item3cc18f8821

Or maybe do something different and buy this. Has a VK EFI 202 conversion ready to go (keeps the van more original as a 6cyl):

http://www.ebay.com.au/itm/holden-hj...item4161f0fc8e

Or buy one of these and wreck them out, using the running gear:

http://www.ebay.com.au/itm/WB-HOLDEN...item3f132354e4

http://www.ebay.com.au/itm/holden-hz...item3f12d96f4b