Are you talking about the square ones or round ones for the bolts ?, on know the rear square pads near the fuel tank were adjustable on an RRC but not on the D1 and mine dont reach the body anymore.
I built a simple frame from alloy tube and made the slide from the same tube with gal steel rods for the fridge to sit on, i used a couple of 125kg rated ball bearing lockable slides so that once is slides out it locks in position as well as locking when closed. Have since added carpeted plywood to the top and yet to add a couple of drawers in the right hand side.
The tube and fitting are from the hard ware and just push together, quite sturdy but i added rivets to help hold it together.
Get it crack and hardness tested and if it passes go from there, plenty of people get away with a light skim and reusing the head.
I did this to my tdi head and all good after nearly 20k.
I went to a property here 18 months ago where the owner bought up all the spares that the Aus Army were offloading when they went to Land rovers for their vehicles, he has crate upon crate of new diffs, gearboxes and transfers, engines all wrapped up in greased paper and crated in transport ready crates.
He also had at least 12 complete vehicles in various states of neglect and running.
Hopefully the V6 Rok have a bigger oil cooler for the auto, been out on a few night time rock crawling trips and we constantly had to stop for the 2 Amarok's in our group while the auto cooled down.
They do look like a good unit.