Now that I have done the LI-Ion batt conversion, I need to do something about the suspension

[Kingfish]

The conversion took about 350lbs. off the vehicle.  It never rode great, but now I feel every  crack in the road.  I have backed off spring compression nut to the point just under where they would move around if suspension was at full extension, but it is still very stiff.  I would like to put some softer coilover springs on it, but I have no idea what the spring rate is with the original springs so I would just be guessing on what to order.  Does anyone have the data for the original spring compression rate?  I am willing to give up a little ground clearance for a softer ride. Right now when sitting still the rear suspension is at or near full extension and the rear tires have several degrees of camber which will cause uneven wear if allowed to continue in this state.

[Osney]

I'm in a similar position, having shaved a mere 230kg off by my DIY lithium ion battery replacement! I know very little about suspension setups though, so really not sure what to adjust.