I have a guava tree that started producing nice fruit this year and I was wondering if I needed to do any pruning, and if so, when would I start and which branches should I prune? I am aware guava trees respond pretty well to pruning.

Here are some pictures of the tree (sorry that they don't show much). I've marked some of the branches as best as I could.

http://i.imgur.com/2s84y.jpg

http://i.imgur.com/IJ4Ir.jpg