Here is a list of some of the instruments David worked on at Grubbs……
48-inch reflector, Victoria, Canada, 1961
40-inch reflector, Pic du Midi, France. Optics only 1962
The 40 inch Elizabeth telescope. S. Africa 1963
74-inch reflector, Helwan (Kottamia), Egypt, 1963
30-inch reflector, Jungfraujoch, Switzerland, 1966
16/24-inch Schmidt, Castel gandolfo, 1967
The 98 inch Issac Newton Telescope at Grubb Parsons. 1967
72 inch (182cm) Mirror for Padua, Italy. 1973
48/72-inch Schmidt, Siding Spring, Australia, 1973
154 inch Reflector, Siding Spring, Australia. 1974
48-inch reflector, Athens University, Greece, 1975
150-in mirror, UKIRT, Hawaii, 1976
60 inch Reflector, La Silla, Chile 1976