I had always assumed that cars built from 1999 onward, i.e. those with 4 wheel traction control, had 4 pin diffs. However I remember reading about someone who took a front diff apart on a later car and found it was 2 pin, so there is a bit of confusion about exactly which models are 4 pin.
I've got 2001, which is 'supposed' to have 4 pin fitted...
When I removed it (from the PITA the hub was to get apart, I doubt it had ever been done before) it was 2 pin. Don't know if it's because mine was in the last year of production that it was a case of 'chuck in whatever is left on the shelf' or whether the 4pin front diff on the later models is a myth..
Let us know what you find when you get your one out!