Thanks for the link. I saw your thread and was going to ask you about the coils you had... which are you running, the 3935lb or 5000lb springs and are they progressive or single rate? How's the ride with them and do you rub your 265s at all?
I found a set of progressive e-super duty coils for $50, I think I'm going to give them a shot to see what I get out of them as far as ride height and ride is concerned. The only spec I can find on them lists them as 6000lb springs for the set (3000lb each) but I'm assuming (hoping) this is max load and the first few inches of suspension travel aren't back breakingly stiff...
On my quest for factory spring info I found some specifications in the 'Ford Truck Body Builder Advisory' online:
https://www.fleet.ford.com/truckbbas/to ... specs.html
Though there is no spring code break down it looks as though there are over a dozen different springs to choose from that would be heavier than what I'm currently running, too many to choose from at $200 a set so if my $50 springs don't work out I might be better off just going the route you did.