I'd now reached a point where there was no real reason not to put on the timing belt. The remaining work can all be done with everything in place, so it was finally time to make it look more like a working car engine.
First up, on went the timing belt pulleys - the idler pulley went on the right, and then the tensioner pulley on the left. The tensioner pulley pivots on a notch on the pump, and has a pulling force applied to it by a spring that's latched to another part of the pump. This spring is what puts the tension on the belt. So, when putting the tensioner pulley on, I pulled the tensioner right out of the way and then only nipped the tensioner bolt up a little bit - just enough to lock the pulley in place so that it placed no pressure on the timing belt.
The crankshaft requires about 116ft.lb of torque, so I needed some way to stop the crank rotating. What we did was brace the crank at the rear by using 2 old flywheel bolts and a long, tough screwdriver (the widowmaker makes a reappearance!). The screwdriver was placed so that the bolts 'locked' onto the screwdriver:

So, I slipped the timing belt around the crank cog, put the crank timing plate on and then followed with the crankshaft bolt. The screwdriver prevented crankshaft rotation while I torqued up the crank bolt:

And now to finally set the timing. First, we align the crankshaft to the timing mark on the oil pump:

And then line up the camshafts. Here you see my previously mentioned patented (cough) technique for camshaft locking - grab two shifters and turn the crank so that a) the E and I on each camshaft lines up with each E and I on the black timing plate, and b) the shifters overlap when condition A is met. If you're soloing this, then you need a clamp that you can operate single-handedly, as it's expected you'll be holding the shifters with one hand, and the clamp with the other. Once it's clamped, you should end up with something similar to:
