Like literally hit it with something, sometimes it gets extremely dusty or the connections become disconnected so by hitting it you are knocking the dust loose. By you saying it clicks only once or twice means you have power but you aren't turning the starter.
Yeah as granitex said get creative with 3/8" extensions. Its been a super long time since I removed those bolts but I know I used some super long extensions to get the ratchet in the clear.