great triple post there wink. notice the "edit" button? use it next time.
anyway. Spartan, for the dean head and the stock "hole" just drill it out a bit until the deans head fits through. and you could spend the cash and pick up a nice stock KWA or even better a G&P but only if you truely think it will be worth it. any type of "Upgrading" internally of a gun is a pain in the ass the first time around, and its something you just need to get used to, like they say practice makes perfect. to bad in airsoft practice means wasting money most of the time.
if the motor is your only issue in the gun I say stick with it. get the motor replaced, fixed, or just buy a new one. shed a tear for the lost money and move on. trust me most of us have had to do that at some point. I bought a $80 motor and it was DOA and evike more or less said to bad and I had not return chance. so I shed a tear and moved on. sucks but it how it goes in the tech department. good luck however, and if you want a Systema A-Z or a stock G&G motor let me know.