All shows have slightly different requirements for staging entries, Bobbioddsocks, and I would recommend that you contact the Show Secretary. We show secretaries want as many people as possible to enter the show and are as helpful as we can be with queries like this.

You tell me in a pm that it is a small, WI show with no set rules.
I would display the fruits on paper plates, plain white with no pattern. The idea of the exhibit is that it should look as attractive as possible to the judges. With the currents I would look to see if you have a bunch with ten fruits on it, otherwise two with five fruits and fan it/them out neatly on the tray. I would not top and tail as this could lead to bleeding on the tray. With the gooseberries leave the tails on and trim the top to leave a short stalk, exactly the same length on each fruit. If you are allowed more than one entry in each class you could also make up a plate of individualy picked currents treated the same as the gooseberries.
Just have some fun with your entries and good luck.

Thanks Bulba - needed to know this too.