Looking great dee. I bought that kit last year so I could butcher it up and turn it into two scratch rockets. Curious what motors you are planning to fly her on.
I'm impatient so prolly not the best person to ask, but I would wait as long as you can stand it before applying the decals. These were the first waterslide decals I've used since I was a kid and they ended up not going on either rocket, lol. To me, the sniff test is the only way to know that the paint is done curing, but it could take weeks depending on where you are keeping the rocket.
After about 2 days the surface I think is more than good enough to slap them on there though. I'm in the same pickle, I have my first full-cure primer layer on my L2 rocket and my sanding fingers are itching to clean up the fluff and spot fill any little depressions, even though I know I'll just end up wasting sandpaper and clogging it up. I'd focus on the chute, make sure everything is good to go, and find a way to distract yourself for a few days at least.... maybe a new kit to start on???? lol
Good luck with her. That kit is kind of impressive for the price.