Outer Limits 4x4 Board

I have a 2.8 gu patrol(about to be a 5.7lt)and i have purchased a 4.2 gear box and transfer case do i need to change the tail shaft or will the one i've got match?

no just swap the flange and drum from the 2.8 transfer case to the 4.2 transfer and your shaft will fit otherwise you will have to get a 4.2 shaft and diff flange which would be better anyway as their stronger

cheers mate