Thanks for the comments, folks.
I cannot claim the paternity of the standup servo idea - actually I saw it on RC10talk first, can't remember if it was GreenHell or Grizzly, but I believe one of these two. Credits to the initial "inventor". I think it's the soundest possible solution, which obviously wasn't on the radar screen at the time of full-size servos.
Thanks RCChris for spotting T2 hubs. Can't believe I didn't see it myself, to be honest. I need to find myself some proper 6360's, shouldn't be an issue thanks to the re-re's. Thank you.
Ok, prepping the TBG 10T body for paint.
First, window masks. rather than cut them on the body, I did some templates in paper and then used these templates to carve masks out of whatever sticker sheet I had available: in this case a lowclasscc (is it still a forum sponsor btw? great stuff back then!) chassis film protector leftover.
Position paper on body with tape
light from the back so you can see the window-edge shadow on the paper
Cut the die:
Cut the masks:
Masks done
Paintjob. I can only do one paintjob, it's the one that's been adorning all my offroaders for years, the good news is I master it about right now

This one (on my Xb2). No PRP or CDPaint job, but it does the trick once it's plastered with stickers
Masking in Progress:
Painted, but still with that blue protective sheet:
Haaaa, now it's yellow and not green
And, fitted, but not decorated:
Then I went off to my sticker sheet cupboard, only to find out that I didn't have that spare 10T sheet I was hoping for... and MCI is closed till May 30th, grrr....
I guess that'll leave me some time for gluing those tires. Other than this and a mising pinion, the car is ready to hit the track - which I don't have any of any more
Almost done...
Paul