Last transmission bolt - TDC

Put two bolts back into the bell, jack the trans up until it hits the floor, then you should be able to get to it from above. You'll probably have to bend the tab that holds the wires for the neutral safty switch to get a box wrench on it though. If you manage to get a wrench on it but can't break it free try a few good taps with a punch or blunt chisel.