My '37 has slightly lower spring, not on purpose, but I had new ones made with softer spring rates so the set a bit lower. Ride is much better, but around where I live there are a bunch of speed bumps to control traffic. The front will bottom out pretty easy on the speed bumps, but normal roads are just fine. I have a sway bar on front but did find the cornering is a little better, I don't feel like I'm going to roll over. I don't carry any load so no information on that.
I would talk with Eaton Detroit, I was happy with them. Be prepared for the cost, they are not cheap! I was after a softer ride, so I borrowed a set of four corner scales and weighed the truck with and with out occupants, and sprung weight and unsprung weight. In the end, its was around $300 per spring including the shipping, maybe 7 years ago, don't remeber for sure how long its been.
They can make anything you want.
Joe
