Thanks guys, and I'm a tad embarrassed to report that there's nothing wrong with the saw, only with my brain. Apparently you actually need fuel in the tank to keep it running, regardless of the amount of fuel in the clear "priming bulb". Oops........
Anyhoo, it was quite a nice day today, and even though my back gave out after only 3.5 hours, I got a fair bit of stuff done. I did some work on the tank (forget about PDR tools unless you know what you're doing, I was worried that I'd bend the fuel filler hole, so gave it the arse and bondo'd up the few shallow dents) and was happy to find two small cans of the blue that I used on the F2's tank last year, which is actually very close to the OEM colour for 1974 I think, but I am color blind. (seriously) I'll have to buy more as these are really only touch up cans, so I can spray it on and then compare it to a pic of a restored 1974 blue T500, and if it's too light, or if I just don't like the shade I can still use it as a primer coat.
I pulled both fenders out of the phosphoric acid bath, and while the chrome is buggared, they're not rusty any more, so will be fine until I can either get them re-chromed, or find some better ones. I also pulled the nice clean fork springs out of the bath, washed the acid off, dried them in my oven, gave them a cleanup on the wire wheel and hit them with some WD40, and will re-install the forks into the triple clamps tomorrow.
As previously mentioned I mixed up a litre of 40:1 two stroke mix and fired up the chainsaw, and was happy that it cut thru a couple of thick branches like butter, but as no one was home to take me to the ER if I accidentally cut my own head off, I thought it best to put the saw away. Yes, strange but true, I'm finally becoming careful....... My back gave out before I thought to take some pics, but the weather is supposed to be even nicer tomorrow, so I'll snap some pics then.