It is snapped close to the housing? if its a few mm left, try using a wire-cutter or something. Also, you could try sliding it out from above, using a screwdriver & hammer, as you shuld be able to se the pin from above.
Probably not too much space around tho.
If your speedo don't work I guess thet the gear behind the diff has given up, so the box need to go out anyway