i need some help
 

im lookin at buyin a 03 duramax with a 6speed manual. the guy said that oil leaks on top of the motor. the injectors were replaced about 40k miles ago and i assume that the leak started soon after. i was thinking that the valve cover gasket is leaking or something like that.. i was also thinking a turbo oil line or intake manifold gasket or something. just wantin some ideas if anyone could help out! i'd appreciate it!!!!

there aint much to fix up there on the top of the motor, i had an oil leak when i took my truck to get the injectors done at the dealer, there were a few loose bolts on the valve covers it fixed easily.

the only other place it could leak up top is from the turbo

so basically unless its a cracked block, which would be noticable, its nothing major and easy fix?? sweet thanks for the help!