=== Difference 3 - Neck Plate Pin Slots
Here's something very strange. On Megatron you can clearly see some slots that make sense. The slots are uniform compared to most I've seen to accommodate pins. The pin here is pretty standard, with the rough bit at one end to anchor it.
On Predacon however, these slots are missing. But more puzzling than that is the pin. It seems that the pin (which I've yet to remove) is sitting loose in neck plate, but rotates with the L shaped piece. It seems that the rough bit to anchor this pin is located closer to its center, somewhere in the L shaped piece.
=== Difference 4 - Elbow Joint Hole Size
Here's a minor nuisance in swapping the parts.
It seems that the hole size for Megatron's forearms is slightly larger than the hole on Predacon's forearms.
Now this is bad, but it could be worse. At least the hole difference is in the right direction. In prior tests, Megatron's forearms will fit on Predacon's biceps, but they sit loose.
=== Difference 5 - T-Rex Shoulder Plate Mounting Pin
This will definitely be a nuisance. On Megatron, these shoulder pieces are held in place with pins. This may not seem like a bad thing, but they're very VERY difficult to remove (I've yet to do this, and I've applied enough force to risk buckling the pieces).
Predacon's T-Rex shoulder plates just clip on. Luckily, the holes remain in Predacon's torso shoulders, so I'm sure that once the pins are removed from Megatron's pieces, they should fit just fine.
