(b)the applicant may, except where he suffers from a disease or disability specified in the Second Schedule, claim to be subjected to a test of his fitness or ability to drive a motor vehicle of a particular construction or design, and, if he passes such test to the satisfaction of the licensing authority and is not otherwise disqualified, the licensing authority shall grant him a [driving licence] [Substituted by Act 100 of 1956, section 5, for 'licence' (w.e.f. 16-2-1957).] to, drive such motor vehicle as the licensing authority may specify in the [driving licence] [Substituted by Act 100 of 1956, section 5, for 'licence' (w.e.f. 16-2-1957).].