743 engines are a piece of piddle to remove.
There are no hidden bolts.
Remove the starter cables and earth lead, the air inlet hose. Remove the fuel and tap off lines and exhaust.
Remove the 4 bolts at the bottom of the engine that go through the engine mounts. I used a small air hoist attached to the 2 lifting points on the cylinder head. You may need to use a pry bar to get the engine loose Put some tension on the engine and pull it back wards and it will come free.
Re-installing it is a bit hard, you need 2 people for this, you will need to lay down over the pump and line the universal joint to engage the drive spline on the pump. Make sure you grease your universal joints before you re-install it!!!!
Any problems just yell, i have an engine to install hopefully this week end.