I just came upon the comment below from 2017 and am reminded of trip to Italy in two Lambdas, John and his friend Brian Adonis and John Turner and me in John's car. We were going to a rally in Varese so had to keep to some sort of schedule but after a few hours of driving in France with John and Brian leading the it became clear to us that we were not making sufficient progress.
It was all very pleasant and scenic along country roads and small villages but we signalled to John to stop to discuss it.
John, it transpired, was navigating with the same Michelin maps that he had purchased for a cycling tour in France during his school holidays, his reasoning being that the towns could not have moved.
All the illustrations were of course of beaded edge tyres and none of any bypass or main roads were featured.
We changed maps and got there in time.
In addition to the cars in the garden and the spares in the house, John had several lock-up garages around the area full of spares. He could be irascible but rarely declined to help a Lancia owner in need. I co-drove his Lambda to Turin in 1971 with him (by which time his health was already in decline. The RIBA staged an exhibition of his photographs, and published a booklet too. His studio when I met him was in Watford Way in Hendon, in the middle of a row of shops.
He was an exceptional navigator and a fast driver, often at the same time.