300 and 240 spec springs are different heights, dont know if they are different coil diameters, didnt look like it. the problem i had was finding any site that sold 240 specific springs without listing it as a general 123 chassis spring for all models. it seems like the default spring you can buy is a 300 spring.

this will give you some serious height back there which is exactly what you say you dont want. if you like the current height, i wouldnt change the springs out. they are cheap enough though you could buy a set, remove the current springs, compare and mark and cut down your new springs a little to get the desired ride height

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