Mustang engine running...

...but that's not quite the end of it. The final assembly of the engine and refitting all went well and, other than gasket error between the PCV spacer plate and the new Edelbrock intake manifold (that was fixed by inverting the plate), it fired right up. I had taken the liberty of priming the carburettor, that helped. I've yet to check the timing and the idle mixture might need a tweak to match the new engine but otherwise it sounds nice. After a couple of starts the starter motor began misbehaving so the owner bought a high torque option and this was fitted yesterday. The last thing he'd asked me to take a look at was the rear axle, he'd had some work done on it elsewhere but it was noisy and he was worried the crush sleeve on the pinion had been over-tightened. I pulled the prop out this morning and found the pinion assembly was actually loose with 1-2mm of float. I've removed the carrier and stripped it down and have some parts coming to see if it can be fixed.