You've got some really great advice here. To make hand feeding less intimidating for you, hold the food in the palm of your hand with fingers/thumb together and your hand flat, like a plate. Use the "gentle" command every time.
How about an obedience training class? You are to be commended for working hard with your bully and not giving up on him. One other note... I was told by my vet NEVER to put a muzzle on a bulldog... just thought I should mention that. Of course, my vet recommended a harness instead of a collar too. Basically, nothing to restrict their breathing. Good luck.