You can shot some gloss clear over it, and it will give it a shine, I would not recommend you use the lacquer clear over the enamel, you can, but you would have to build it up using a lot of mist coats, if try doing in one coat like it the can says, it will make the enamel run.
Testors does make an enamel gloss clear coat, and you can use the one coat in your A/B, just decant it from the can, thin it with lacquer thinner.
Did the green you used, was that shot thru your A/B?, if so , what did you thin it with it, if you thinned it with a lacquer based thinner, then you should not have any problems using the one coat over it, just do not try to apply it in one coat, and the one coat stuff isnt really one coat, you need two really. But its a nice clear coat though