Well i've been quiet for a week, but only cos its been mainly sunny weather !
Had rain showers overnight twice this week and both occasions i was greeted by water ingress again - at least i can be certain now it does leak when stationary as well as when in motion.
I'm keeping a large microfibre cloth stuffed between the fusebox and the outer metalwork of the passenger cell to absorb the leak - this morning probably wrung 150ml of water from the cloth

I washed the car last night too - i'm certain it isn't the windscreen in any way now, as pouring water into the sctuttle area at the poitn where the drivers side wiper arm attachs leads to water drip every few seconds to the right of the fuse box inside the cabin. Given that i've pretty much undersealed any weaknesses in the scuttle area i think i'm going to have to further investgate the drivers side wing attachment area - I'm probably going to remove the front wing next week for a better look, undersealing the outer face of the joint with underseal hasn't reduced the ingress at all. (i'll have a bit more space in the garage by then).