I prefer rolling, but I don't have a Zaccaria cab.I use small foam rollers.
So far I only had to do black insides of the monitor area and the back of my Ms.Pac. Looks nice IMHO although I didn't study it up into minute detail. After all it's "just" the back

O wait I also did the Galaxian insides on the top (not the top itself)....
Anyway, all these areas not too critical.
I still have the DK red challenge in front of me (stirred and turned over the pot again....this paint is getting old

)
Getting that as smooth as the original is going to be close to impossible I guess.
Surprised to learn the Zaccs didnt have a primer coat ? Even if that is so, I would personally still do it, it makes it a lot easier to get a nice even coat, you won't need as much final paint and the paint will bond much better. Just MHO of course.