1996 Chevy Blazer starter

Electrical problem
1996 Chevy Blazer 6 cyl Four Wheel Drive Automatic 195k miles

i HAVE REPLACED MY STARTER IN MY 96 BLAZER NOW THERE WAS TWO WIRES A BLACK WIRE WITH A METAL RIM AND A GREEN WIRE THAT WAS STRIPPED AND ALL IT WAS WAS ELECTRICAL WIRE THERE WASNT ENOUGH REACH SO I BOUGHT SOME GROUND WIRE FORM AUTO ZONE AND I ADDED ON TO IT NOW I TOOK THE GREEN WIRE AND I PUT THAT AROUND THE SMALL THREAD WITH THE SMALL NUT ONT HE STARTER AND TOOK THE BLACK ONE AND MOUNTED IT TO THE BIGGER THREAD WITH THE BIG NUT, BUT NOW MY BLAZER SOUNDS EITHER ITS TURNING IN REVERSE OR GRINDING I DONT KNOW IF I WIRED IT WRONG OR IF I DIDNT I CANT FIND HOW THE TWO WIRES GO ONLINE, IW OULDNT BE ASKING IF I TOOK THE OLD STARTER OUT, IT WAS ALREADY OUT. CAN ANYONE PLEASE HELP ME?>