Great to see this camera again.
See if you can find a
Motor Drive MA cheap. It'll give you shutter button on vertical grip position plus second shutter button to shift from single shot to multiple frames. Motor drive will add that weight for better grip and feel too.
Canon used to call it
hexa.photo.cybernetic 
for it's multiple shooting options.
It gave me great results for years. Remember having great time doing stage photography with 85 mm, 1.2. Seldom one needed to push TRI-X beyond 400ASA.