so if the fuel pump is running when you turn the ignition on...

there is a spark, but only at number 1,,

the timing is correct,

have you checked the multiplugs along the back of the engine bay, near where the interior fan draws air in, these can get corroded inside and cause all sorts of problems,,,

may be a silly one, but you do still have the carbon pip in the top of the dizzy cap don't you, they are famous for flying out when you remove the dizzy cap as they are spring loaded...