Hey, I have a 1991 LX and I was planning on purchasing this kit, right now it's basically stock besides a cat-back and a paxton 1220 charger. I was told that something to do with the heads will not work on a 1991 motor? Something to do with lifters? Is this true? I just don't want to spend almost $3000 dollars to find out that I'm going to need to spend another $2000 to make it work. Thank you in advance for any advice you can give.