Strong work as ever Dan. Please send me a few of the spare hours you appear to have floating around. Currently I seem to be averaging about 27 hours per day!
When I finally got around to entering the world of work I had a couple of conditions. No suits and no having to work really hard...

(although only the other week I found myself in a suit on the early train to Paris. Bah.)
My bus will happily cruise all day at 120kph (75mph). It'll spin up to 130 no probs at all (81mph). I've always lifted at that point so I'm confident the 21 year old girl will achieve the 85 figure. Max torque seem a bit feeble. Blame the lack of boost for that I guess. Lets hope we never need to drag the skin off a rice pud !
I do like the five cylinder lump It's so sweet. It's happiest at around 115 kph. (38mpg av).
I'd really like to build a new unit for the bus. Balance/blue print everything. Mines covered 365k kilometres, doesn't use a drop of oil and runs beautifully so it's hard to justify taking it out to refurb it.
You've got a good 'un there I think.
Mine was very agricultural, used to make so much noise at 65 and economy dropped after 60 (best I got was 34mpg). Sure the turbo didn't help, but I think we know now that my engine has had a troubled life, despite the almost complete VW service history. I've also learned that the very early vans have a slightly different version of the AAB and the cooling system is different.
Westfalia also varied the base vehicle they used when building the Cali. Gearing could be different, and weight - mine has glass double glazing in all the back windows. They also did a version with plastic double glazing and no window behind the wardrobe (which looks like what you have?), I imagine there's a big weight difference there?
We'll see how it runs after the rebuild (and we're back to NA now as well). Got the case back, that's been skimmed (minor depression next to #3), so it's back with my usual mechanic. Who's hurt his back. Nothing happens quickly in my world
Anyway, ought to do some work now...