Well, I finished routing out for the SD NY4 pickups, which required widening the routs then filling in the ends on the bridge position pickup rout with some basswood, and then routing it out again so the pickup just fits in. The neck one just needs the right-sized hole in the pickguard.
My first go at routing a new pickguard (the NY4 pickups are shorter than standard JB ones, so I couldn't rout a normal pickguard) ended up with a piece breaking off both the pickguard blank and the pickguard I was using as a template. so I have yet to re-do that.
But I did apply a light mist coat of sealer/filler, which I'll sand down to see how flat I've got it. There are a couple of small areas that have shown up that need a touch of filler, but otherwise it's looking good.
I did it without the spray tent as I'm sanding it all back, so wasn't worried about dust, but the new spray tent arrived just after I'd done this.
I changed my mind and it will be sprayed Sonic Blue, rather than Daphne Blue, as I think Sonic is the colour I actually wanted my refinished Strat to be.