AK upper receiver trouble
 

ok...so I purchased a jing gong AK, and just recently bought a metal body here off of the classifieds......but I'm having trouble putting the whole works together.
It would seem that the upper receiver (the bit with the charging lever) will seat nicely on the metal body....however I CANNOT get the metal rod that holds the top cover on to fit into the forward hole with the spring.

OR

I CAN get it in the hole......but then the upper receiver will NOT seat onto the metal body.

any ideas why this is so? I even tried the upper out of my Kraken and it's the same sort of deal. BTW, it's an element body I'm using. What should I be doing to get everything to fit???

my element body needed a little bit of dremelling in the selector section, maybe you it's the hole you will have to dremel out or... check the little notchs where the bolt carrier sits, i had to file mines to have the carrier to fit perfectly... if you could take a pic it would really be helpful to determine where to work