Sounds like a great trip ..... if you're doing Scotland, a couple of days in the NE (Grampian) is an overlooked gem ... some great roads and hopping the series of fishing villages under the cliffs from Cullen to Pennan is a brilliant day ... and much quieter than the more known places in the summer .... let me Know if you think you might and I can give more detail.
Prescott is brilliant (Graham can give you more info) ... a fine Bugatti Museum and always some old racers on the hill... one of my favourite venues to drive and just hang-out .... to me a 'must see' would be a British Championship round at Shelsley Walsh ... the place oozes atmosphere (they've been hillclimbing there for over 100 years) ... the speed of the top single-seaters on the hill is astonishing, and on a sunny weekend the spectator's car park has a free car show of classics ... place is iconic.
K