I think you might need a 4 and that set only goes down to 6.
I'm not at work today but i can check tomorrow.
They are worth having though. They use them a lot now. Check out all your door catches and latches.
Did folk go for the above sizes for hole 50x50 or did folk use the fittings on the fools link below it. As I found 50 mil was to high as it has a ridge on outside which doesn't let the bracket sit flat against van. 34 seems more like it.