Right, after spending a small fortune in Halfords and heading up to the site, todays work is at and end.
Shopping list:
Castrol Oil 4l x2
90 piece tool set
rubber gloves
oil filter removal tool
overalls
large plastic container
wd-40
screwdriver set
distilled water
wyns fuel system cleaner
Your very own amature mechanic in a box
Firstly I removed the battery as instructed in the Haynes manual. The battery tray appears to be in very good condition. It was pretty much all still coated in the original paint with no signs of corrosion. The only bit that is bad is the bit that fella spotted in the photos (one corner).
Then I checked the new battery, electrolite still appeared to be covering the metal plates. I stuck a little water in just for good measure and then set to work installing it in the engine compartment.
Started the van up and happily it started first time.

However the battery low light stays on, even after I left the engine ticking over for 5 mins.
Will I need to go for a long drive to get it fully charged or could this indicate a problem with the alternator / other?
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With that completed I decided I would attempt to remove some more of the plastic covers on the floor inside the cab.
I was able to remove the triangle shaped covers that sit just behind the wheel arches, before the foot well. Low and behold there were signs of corrosion under these parts.
Looking under the van, at the bottom of the wells and this area I had just exposed, all you can see is the black (underseal?) coating. I am guessing some heavy duty work may need undertaking in these areas depending on the extent of the rust behind the outer coating.
Stupidly I forgot my camera so photos will follow when I am next up there.
For my next trip, I will look into what I need to do to change the air/oil/fuel filters correctly. Air and oil seem simple enough. Not sure about fuel.
Many think that is confusing me is the differing advice in three places regarding which oil to use:
1) here
2) haynes
3) owners manual
In a little while I will post what all three say side by side so we can try to get to the bottom of this. All I want to know is if the oil I have purchased is going to be right for the job. I'd rather have the absolute correct oil in there though.
Crazy BT van man.