Been trying to get the engine out again today. Decided to try and get the engine out without the gearbox as the underside of the car is badly rusted and I don't really feel very safe working under it while it's on axle stands. I tried getting the prop shaft off the gearbox and again the bolts are badly rusted and stuck tight and it seemed to groan a bit when I tried using a hammer and wrench to loosen them. So I thought it would be best to leave the gearbox and bottom of the car for now and get the engine out, then flip the car onto its side to get everything off the bottom of the car. Problem is when I tried rocking the engine forward and back to release it from the gearbox it wouldn't budge. I can't see any other bolts holding it in and I had my wife doing the rocking while I looked around the seam to see if it was seperating anywhere and it wasn't

Can anyone shed any light on where I'm likely to be going wrong? I've lifted the engine clear of the studs on the rubber bits holding it to the chassis so I know it's not stuck there...