Any sort of gloss varnish first is great. I actually use Klear floor polish (works good as a seal for oil/turpentine washes too).
I think i used sol first to soften the decal and smoothed it over the shoulder pads, then set to re-glue/set it when happy with positioning, and then when dry a matt finish to take off the shine. It has been a while though.
Pin vice drills are usually fairly cheap. In the UK at least. I can see some for £4.95 with free P&P & 20 pin drills included. I couldn't cope without one, barrels aside I couldn't pin any resin components to plastic ones, or do leg extensions, or keep heads detached until I was absolutely sure I had the facing right.
If you do get one just remember any excessive shearing force and they snap, whether titanium coated or not, and then you end up gouging your fingers. Less likely these days with white metal gone the way of the dodo but the amount of times I maimed my fingers and needed a tetanus boost due to metallic spall in my fingers...well, that was just twice but you get the idea.
Actually stay away from pin vice drills, they are capricious tools that bite they hand that owns them 
Rambling aside keep at it, those Primaris look great.
Any of the multi-part kits tempting you?
I had used my big power drill for magnetizing a leviathan and somehow managed to do it without drilling into my body parts, lol.
I'll be grabbing a multi-part kit of the intercessors because i want a third squad for my battalion detachment. Not sure about the hellblasters or inceptors. As much as i like the inceptors, i find them hard to work into army lists due to their expense.
I'm with Marius, when do we get to see your take on Aggressors/Inceptors/Reivers? Admittedly, I think the models are
personally, but if anyone can pull them off, it'd be you.
Oh don't you worry! I have a squad of aggressors next in line and the DI inceptors sitting on the tray too. I love the aggressor models, so i'm pretty excited to work on them.
Have you seen the inceptors in person? I thought they looked pretty wonky in pictures, but in person i really like them.
I've got all of the primaris models so far except the rievers (hit a snag ordering them then didn't get around to re-ordering). So they'll all make it into this thread at some point.