[FLASH 8] Picture gallery help needed

I’ve created a picture gallery that works like this:

I load all the images into the movie on the first frame into thumbnail movieclips (“1” to “4”), like so:

loadMovie(“images/1.jpg”, “1”);
loadMovie(“images/2.jpg”, “2”);
loadMovie(“images/3.jpg”, “3”);
loadMovie(“images/4.jpg”, “4”);

Then when you click on a thumbnail button:

on (release) {
place = “images/1”;

it loads the corresponding pic full size into the main movieclip (“large”):

loadMovie(place+".jpg", “large”);

My problem is, I need to create a “previous” and “next” button so that once an image is open in “large” you can just flick between the pics without having to go back to the thumbnails. Can anyone help please?