It always goes behind my wife (5' 2") rather than me (6')!
You have to move the head rest out of the way, but other than that it's a really snug fit, one of very few chairs we were happy with as it fitted so well.
We've used it in every MINI, first and second generation, soft and hard top, cloth, half leather and full leather.
The only version it didn't fit to the seat quite so well was the Convertible (in terms of seat base to car seat), but it still held very tight, you just needed to be a bit firmer with the seat belt attachment to squash down the 'bulge' in the middle of the seat more.