Lift kits for K30? (spring widths)

[napcoguy]

I am wanting to add about 2.5 inches to the height of my 84 K30 and I am having a problem finding a add-a-leaf/lift kit that is designed for the K30(454). I have seen pictures all over the internet of lifted K30's but I cannot seem to find a system. One issue I am having is finding springs that are 3" wide, all the kits I have noticed are 2.5" wide.

From what I have read most folks think or say they are the same width on all the 73-87's and some say there K30 has 2.5" springs while others are equipped with 3" springs.

Does anyone have any information on why some would have 2.5" while others would come with 3" springs? also if anyone has any information on a small lift that would be great.
Thanks