No CAD/CAM back in the days of men in brown dustcoats in Weybridge or Hurn, hand-crafting against drawings.
I've read that the difference in handling between members of the BMA Viscount fleet was marked.
G BMAT was a sort of "cut and shut" from G-AZLT (written off at Leeds) and G-BAPE (I think), put together with care by the lads at the Castle Don. hangar.
By luck or judgement, I heard that it handled better than any on the fleet.
And those nodding nacelles! As a youth, I used to think they were about to drop off.