Built another one a while back. Upgraded to 24mm mount and added a plywood front centering ring, Qualman baffle and replaced the plastic coupler with a normal cardboard piece. Made the upper section a payload bay.
It turned out nice. I have one for a future build and using R2X flat gray primer to spot imperfections then two light coats of flat white primer on my recent builds. Are you using the newer krylon? I was going to buy some the other day and they had the Fusion 5 and the Color Max, wasn’t sure which one.