Frets are in. Ended up making a fairly crude but very effective radius jig. Definitely made it easier to get them in. Basically you slightly bend it by hand to get it to sit in the blocks and then just pull it through. The line on the paper is a 12" radius, if you look the blocks extend slightly above and below, so as you pull the wire through it bends it slightly past 12". They flatten back out as you tap them in. Not my jig design, I found it online, but thought it was worth sharing.
I'm reasonably happy with the job, especially as it's my first go at it. Certainly on par with the PBG necks, with a level and dress I think it'll be fine. I have actually trimmed the edges overhang and made sure they are all tapped home properly now, currently wicking some CA glue in the slots. Will put a pic with the next update.
So really, I just have to refit this neck to the body and make sure my marking for the bridge is still OK. Then I can do some more routing and drilling on the body.
I think I will then do an assembly to the point that I can confirm the intonation works, before pulling it apart and getting stuck into finishing it properly. I can see light at the end of the tunnel now. Still not entirely sure I'll have it done before the year is out, but pretty close to what I had allowed.