When we did mine a lot of people said take the dash out. Driver sides not that bad and only needs a notch but passenger sides a different story.
The guy that did mine split the dash about a inch under where the pad ends. The pad never sat flat after and because of some other issues I had the dash replaced when I painted it.
I added the cross bar so I could run engine bay bars. If you do the cross bar make sure the chassis guy has the gauge cluster. My bar is actually tight to the clear plastic. Took a lot of work to make it fit.