Dropping the rear of my 64, what to use.

I found someone who makes springs and sells them on ebay. IM going to get de-arched springs for way less then alot of the other places out there,$160.
His shackles are alot less then some others also, only $24 for both. I think he goes by springking on ebay if anyones interested.
The two inches should get me back down where I want my car, but Ill always have the 1.5" with the hangers if I need to drop it further.
I have a desire to keep all the wheels and tires the same , 17x7 with 4.5 backspace. If the tires come too close to the springs, I think i can get a spacer to move them back out away a touch.