Installing a 60/40 sink where we had a 50/50. I need to know if we will have to install new pvc pipes for the new sink, or can we possibly adjust the positioning of the existing pipes to reach the drain on the 40 side? Any advice is greatly appreciated!

You won't know unless you measure and maybe not until you try the install. Is the sink the same depth? Deeper sinks can require new wall plumbing depending on the wall connection. I did a 9" deep last week. Had to cut every drain line and P trap connection by 3". Garbage disposal can be an issue if too low,it will stay full of water.

You will have to make a small adjustment. You can swing the trap in the direction of one drain outlet, then install longer arm to reach the other side of the sink. Depending on the depth of the two bowls, you may also have to install longer tail piece.

Tubular PVC or ABS are relatively inexpensive. We replace them automatically, with each new sink installation

Hope that helps

Milo