I have the exact set up you are looking at on Walter. The Fenton headers with duals, glass packs and a cross over pipe. I had it installed first without the cross over and then went back and had it added. I actually like the sound better with the cross over... my 2 cents worth.

1964 Chevrolet C-20 Fleetside, Otis
1950 Chevy 1/2-Ton, Kirby
1950 Chevy 1/2-Ton Shortbed, Walter