The wheels are a bit of a challenge, as the correct diameter just isn't available - nobody makes a 5'1" wheel, and even when Sharman was still in business he didn't have an appropriate pattern - and the nearest equivalent recommended by Des is a slightly larger diameter.
Most of the time, this isn't a problem unless the wheel centre makes the whole thing look bigger than it actually is.
EDIT: the instructions mention on page 2 the source of MJT hornblocks as still being in Croydon. This is somewhat out of date, as the MJT range was taken over by Dart Castings years ago. Des knows about this, and is updating the instruction sheets accordingly.