getting work done on the final stages of making my 86 trans am 5.0 a daily driver, and i ran into a problem to start off, i had been driving it with a permit to pass the smog and it ran fine, but i knew it would need some money to pass the smog. it turns out one of my cylinders was not even functioning. long story short, i got my engine rebuilt, got a new O2 sensor, new catalytic converter, got my radiator flushed, changed the fuel pump, and passed the smog but now my car has started to fail. it overheats tremendously and after a couple of minutes of being on the road it does a jerking, dropping sort of movement and no longer has any power after that. coudlnt rev past 2.5k RPM until i suspected a faulty cat and tested the car with it removed. even though I can now rev past that old limit, i still have no power once the car does that dropping sort of movement(kind of like i downshifted). spoke to a friend who works at a dealership and he said he had the same problem on a camaro, and noticed that the HEAD GASKETS seemed to be wrong. took the heads apart and noticed the attached picture. the small holes don't seem to be sufficient enough for the passage it needs to get through. anyone have this problem or have any comments on whats going on? any idea would help

woah thats definitly not right, i have no idea why anybody would put that on an engine. Purchase the correct gasket, no worth cutting the holes and reusing it

i failed to mention: the reason why i posted is because I just purchased the "correct" ones, but i opened the package and noticed that they were the exact same ones that i have pictured. the advice i was given by the friend was to just cut into these gaskets(purchase new ones and customize), but I would like to know if anyone else had this problem and if maybe someone knew why I keep getting the wrong gaskets for my engine. has some previous owner changed something?

sorry for leaving that part out