Gents, to get you back to a reasonable ride height you should be between 4 and 5 inches in the front for street driving and an additional 1/2 to 3/4 inch for the rear. Lots of different approaches out there so this is why I am leaving you so much wiggle room. Some people balance oversteer/understeer by shifting weight from one axle to the other, some people track their car, some don't. Street ride is always better on the higher side.
Now how to measure: From the Frame to the ground at the axle line for each end. You can place the car on a 4 post hoist and bounce it a few times to remove friction, then place a level or straight edge across the ramps and measure to the bottom edge from the points on the frame we just discussed, and again, be on the axle centerline, if not your reading will be off.