Best way to adjust rear coil overs for proper height on my SPF

[Pman1961]

I am told that the ride height for the Superformance Cobra should be 27" from finished floor to bottom of wheel lip measured at the axle centerline. My front is about an 1/8" shy...not bad but the rear is squatting and needs to be raised about 3/4". My question is what is the best way to do this procedure if you don't have the proper coil over wrench or wrenches. Would it be best to acquire these tools to do the job or use a blunt instrument and hammer to spin the ring? Can this procedure be done with the wheel on while raised above ground? I know there are many variables but anyone with experience know about how many turns it will take to raise the rear approx. 3/4"? Any advice will be greatly appreciated.