I just got the Wokke chip and in process of installing it but its driving me insane. I got everything done except the two clamp on the side and one horizontal clamp. No matter what i do, i can't get it to come lose.

This is for the EML one. bmw 850i 1991

Also what does it mean to Push Backward on the upper PCB.

Not sure exactly which "clamps" you're having trouble with - (If it's the two at the back of the boards, you can see where they separate in the middle-although each one separated in a different spot) I was able to push the center one back through it's hole by pushing the two prongs togther and jiggering it with a little screwdriver.

I can tell you that it IS an exercise in frusteration as I've done a couple and still haven't found a really slick, easy way to separate the two halves.
I can tell you that everything does have to be loose before you push on the upper PCB.
The top row of connectors is separate from the lower two and connected to the top board-that's why it needs to be pushed back. (The lower two rows are connected to the lower board) Not easy as it's clipped in there pretty good, but a little levering and jiggling eventually got mine free.

Yes i'm talking bout that clip. The two on the side and one on the top. I am stil trying to push it back but no luck.

I have to be doing something wrong. 3hours and no luck.

It probably won't push through until you get the other two at the back separated. The center clip was actually pretty easy on mine - once I was able to push the two prongs together it didn't take much to push it back through the hole.

BTW-on mine this was the easy part - trying to get the upper board pushed out of the front clip is what always drives me to drink...

Thanks for help rockytt but i finally gave up. Going to let the professionals(TxGR8White) handle it before i break anything.