Hi RH, sorry, the manufacturer will not modify what they make. These units are built to a tested design. So, liability risk is not worth it for them to change anything.
You can probably figure out a couple of flat plates to bolt to the existing 'horns" to re- position your seat track mounting holes. Just remember any mods will change the crash performance. Hope that helps.
Let me know if you want a base, I have a few extra passengers right now. thxs!
Beastie 3: 2002 7.3 EB Cargo: Agile TTB, CCV Mid Top, Custom Walk Through, Lots of stuff added. BlingMyRig.com