i've been doing the same thing recently and finally got it flat, it helps to spray a colour paint over the primer to highlight any raises, mine looked fine under primer till i sprayed matt black and you could see a noticable circle
its 2k,
ive just gone an messed up my bonnet now, caught it with the edge of another bit i was moving
maybe time to pay someone to do it dave
i a tit, i lost instructions an mixed base coat with hardner an a little thinners when i was supposed to mix it 2:1 with thinners only
best i write stuff here so i dont forget again.
2k clear has 2 parts clear 1 part hardner
2k base has 2 parts paint 1 part base coat thinners
i already did that an it was wrong colour