Shift cable questions!!!!

Ok i've had this problem on my AOD, there is currently a Hammer installed now.

Now i dont have all my gears to choose from, i have P R R N OD D

I tried adjusting it and its right i'm pretty sure but when going from R to N it doesnt quite pull the lever on the tranny far enough to get into N
so pretty much i take 2 ratchets to get into N and i cant get into 1
There is a metal bracket holding the cable near the shifter, there are some washers placed in the screws that seem to be filling in slack, so i tried adding washers, well i get like 2 drives and cant get into park.

I am pretty sure i adjusted it right, i unhooked the cable from the tranny and then put the shifter into 1 and then put the lever as far as it can go, which is 1 and then hooked it back up.

How often and how hard is it to stretch the shifter cable, ( what causes them to stretch anyway.)

Think installing the stock shifter would make it work??? Are the 2 shifters different? (the box i got from the guy was a shifter specified for an AOD stang)

And if i absolutly need to, i will buy a new cable, are there any places to get them cheap??? the only place i've seen them is on 50resto and they are like 180$ O_O

I just dont want to spend that much money and have it not help a thing....

Well i get opinions and then i go work on it more then i find some more stuff, so i list more details to get a more accurate opinoins. Narrowing things down, i dont feel like spending almost 2 bills on a measly cable....