Thx for all these great responses on my custom Blackout.
As there are a lot of demands for somekind of a tutorial here I tried to create a step by step visual presentation of all the changes that I've made here and hope it helps you understand what i did and helps you improve your own Blackout.
It's not a tutorial but it's the best I can do here.
(if its no help at all, just look at the small decals I used, You can see them very well now)
LOWERING THE SHOULDERS:
I added a 6mm x 2mm magnet (where the arrow points at obviously...)
View of the inside of the cockpit.
A= Corresponding magnet 6mm x 1mm sits behind the plastic and holds the shoulders in position.
You could probably use a plastic peg instead of a magnet
B= I cut away the original "larger peg" - although this might not be nessecary if the mangnet or peg you use to lower the shouldes fits inbetween these two pegs. try out some stuff first and see if it really needs to go.
DIFFERENT BACK - PACK SOLUTION
unscrew the tail and remove all the stuff that makes the propeller work.
Afterwards do not screw back the two screws shown here. don't worry the front part holds everything together fine without these screws.

Now you should be able to remove the tail... do not try to open that up to remove that push button.
It's glued together. I believe I just cut off the bar that is sticking out (if I remember correctly)
If you pull it out and cut it off it will jump back into the tail and dissapear.... hope that makes any sense.
Also get rid of the black joint that attaches Scorponok's cage to the helicopter's tail.

The tail rotor was cut off and stays in place with a simple peg and a hole. Magnets could be useful here but for some reason I didn't use one here.
Be very patient when cutting this off, If you want to go fast you probably just end up breaking the tail.
these parts should be loose like this
the tail itself comes off this way. If the screws are removed as shown in the first picture,
You should be able to open the tail up like this.
that allows you to pop out the end of the tail. close the tail afterwards.
(I can't remember who came up with this trick but I think Shaggy said it best : "It wasn't me")
Now for me it's very important that whatever comes off in a custom goes somewhere else
if you need it in the transformation.
meaning all these loose parts now need to be reassigned.
I drilled a hole so the end of the tail fit perfectly on the peg that normally holds the cage up on the back of Blackout.

I made a hole in scorponok's cage the matches this existing peg altough I have no idea what it does... .... isn't that the thing that controls the deluxe scorponok? well that's not working anymore anyway.
the cage now fits on there perfectly.
[don't make these holes too big or the cage and tail end will keep falling off.]
final look.
Now note that I unhooked off the entire back pack for this tutorial. normally I never need to do that for transforming him.
What is left ? the tail rotor
A magnet was added here an that clicks onto Blackouts arm
I've made a little mold so the rotor stays in place otherwise it would be turning around in all
directions except the one you want. ( remember I did this on the wrong arm in the movie this is on Blackout's right arm - I saw artwork with the blades on this side that's why I messed up)
Im not used to explaining myself so this was weird

Anyway... I hope this helps a bit ...