Glad you got it apart. You may need some tips when you put it back together. It's not difficult but there are some pitfalls to avoid so here's how to tackle it:
When reassembling, lie the shell on its back and make sure the 2 pressure-plate springs sit in their recesses, they fit arched upwards like an upside-down "U". Fit the pressure plate into the shell, with the flat facing the top of the shell and the smooth side, chamfered edge upwards (pretty obvious, I know). Press the pressure plate gently into the recess and slide the innards into the shell. Don't forget to push the RF arm in slightly to clear the top of the shell.
One thing you may find difficult: refitting the inner retainers for the lens mount. Here's a (relatively) easy way, takes longer to type or read than to do!
Lie the camera on its back. Refit the shims in their correct positions, carefully lining up any holes. Lower the lens-mount into place (there's a flat recess on the inside, it must go facing the TOP of the camera), again making sure you line up the screw holes. In what you read below, left and right refer to your view looking down at the camera, lens mount hole facing up.
Now take one of the retainers and find a small screwdriver or pin that will pass snugly through the screw holes. The retainers have a stepped part and one side is flat whilst the other has slightly chamfered edges. The flatter side faces against the inside of the shell and the stepped shape should be on the right of the top retainer and the left of the bottom one. Put one retainer diagonally across the inside of the crate, roughly lining up the top, left screw hole. Pull gently upwards. Pass your screwdriver/pin through the screw hole and make sure it's lined up. Insert ONE mount screw and tighten it up just enough so it's not loose but you can still just push the retainer around. Swing the retainer upwards and use your guide to line up the second hole - for the top retainer, you may have to push the RF arm in slightly to let it move into position. Now, leaving the screwdriver/pin guide in place, tighten the first screw a bit tighter. Insert the second screw but do it up loosely and then loosen the first screw a little.
Fit the lower retainer next, same method as the top except it does not matter which end you put the first screw in. When you've fitted both retainers, tighten all the screws BUT not randomly! Tighten them a bit at a time in an X pattern (such as top left, bottom right, top right, bottom left). They do not need to be done all that tight either, just not loose enough to work their way out later though! The last bit is important because the mount is aluminium and you will distort it if you don't follow the tightening carefully. A distorted mount makes lenses stiff to mount and un-mount and makes collapsible lenses stiff to focus as well. It can also affect focus around the image area, making some parts out-of-sharpest.
By the way, you can also fit the bottom retainer first, it does not matter which order you fit them.
