The TR7 won't start

1) New plugs and leads, gaps have been set and spark seems good.
2) New in-line fuel filter and fuel pump (couldn't get the old pump open to check condition so just replaced it).
3) Fuel has been drawn into the in-line filter so I assume the pump is working. Fuel looks clean.
4) Fires up for a fraction of a second with starter spray, and then dies.
Still won't start. What are the next steps?
It has sat for about 10 weeks since it last ran, and admittedly took a good bit of turning over before starting that time.
I assume next steps are to open up the SU carbs, and check the needles aren't blocked?
The float bowls don't seem to be weeping fuel so I shouldn't need to look there should I, or are they worth checking too?
Any advice appreciated.
Regards
Chris
PS - some of you may have seen my other thread where I was thinking of selling it. Frustrating as this problem is, all the tinkering has made me want to keep it [:)] for another month or two at least [;)]