Gil/hardin manifolds and risers with stock mufflers
 

Has anyone used this combo? I'm trying to figure out my risers as I have a lead on manifolds. I would like to keep my mufflers. I have standard b1 dimensions. I think I need these magnum risers but i don't know if they will line up. I see some old shorty ones but I can't find listing's on any. My mufflers are staggered in out heights. My original manifolds had a 3" spacer for the risers. also what are the seaward series ones? Are they interchangeable?
https://cimg5.ibsrv.net/gimg/www.off...f7af45780b.jpg
https://cimg6.ibsrv.net/gimg/www.off...65a331346a.jpg