I have used the new K&B Ultra Poxy with good results. Straight out of the gun it has a very high gloss.

I then wet sand with 2000 before polishing with 3M Finishing Polish. It doesn't come back to 100% of the gloss, but it is close and you get a really smooth finish.

I particularly like the Ultra Poxy primer. It is white and sands nicely, plus it is very hard and doesn't seem to shrink over time and show the glass weave (I use Z-Poxy finishing resin). No need to spray a coat of white before applying semi-translucent colours like yellow.

Garrett