Anyway to determine spring rate without scales?

[Hotwire]

Need to figure out what rear spring rate to go with, I can buy and swap springs but want to hopefully get close without a lot of purchasing involved.
Don't know of anyone in my area with scales besides the platform scale at the dragstrip, entry/exit is sloped so I don't think I could get accurate rear weight by parking just rear tires on it?



Just installed coilovers up front and am now realizing how soft the rear is w/ factory moog springs. I plan on getting adjustable shocks on the rear and aftermarket springs. Have rear coil spring setup and setting height is pretty simple, plus I'm running 3" exhaust, don't think I would have enough room for coilovers.