So, I agree, bad idea.
But, before we get too crazy on the weight thing- a 426 street Hemi weighs ~843 lbs dry right? And no one would question the guy if he was putting in a 426 hemi.
I’m seeing specs like 1,150 lbs for a 5.9 Cummins. So, yeah, heavier. And lots of beefing up to do. But I’m not sure it’s absolutely crazy.
Right off the bat though, 325 lb/in springs on an HDK won’t cut it. The 2500 springs are vertical. The motion ratio on those coil overs is gonna mean you’re probably gonna need to be 500+ lb/in on the springs