Shortened Rearend on a Mazda

i need to get my rearend shortened 8 inches i called a place around here who does them for hotrods and he said 200 just for the case and he said he had to see the axels to give me a price for shortening has anyone ever gotten a rearend shortened for a mazda how much did it cost? plus i work for a garage so im just goin threw work so i dont know if i can get it doen cheaper than reg people off the streets