Complex sentence: The car was first presented as the Glas 1300 GT in September 1963 at the Frankfurt Motor Show, with volume production starting in March 1964 of the 1300GT with the much rarer cabriolet version appearing in May 1965 and a larger engined 1700 GT in May 1965.
Split into simpler sentences: The car was first presented as the Glas 1300 GT in September 1963 at the Frankfurt Motor Show, with volume production starting in March 1964. The much rarer cabriolet version appeared in May 1965 and a larger engined 1700 GT in May 1965.