The scaffolding is a self-climbing platform, so the wheelchair will be no problem.  In any case, we could always hoist him up into position with a crane.

As for the carving - sounds like perfect practice.  There is another building here with all sorts of bizarre beasts, so plenty of precedent for that type of decoration on the spires ... perhaps we could ship the blocks of sandstone over so he can carve them on the way out.

david