Ok I'll try. Starting with the PSU. Since you picked that one I assume you know Corsair has a very good reputation with their products and their PSU's are recommended a lot. It will also provide you with those 600watts and not just claim it like some lesser PSU's do.
The GPU will require some 300watts on full load so even on a worst case scenario your PSU will still have enough juice for your whole system so it's very unlikely that you will have power related crashes or such.
All PCI-e slots are backwards compatible which means you could put a card using PCI-e 3.0 on a 2.0 slot without performance loss. Your motherboard has a 2.0 slot so you're good there.
I think that is all. Anyway just ask if you have any more questions.
One thing that I'm a little bit worried about is if i have the correct pci express connectors, since im unsure if the gfx card requires 2 . 6 pins or 1. 6 pin and 1, 8 pin. Youtube videos ive seen are showing they have 2 x 6 pin requirements. Could you clarify this for me?
Secondly I had a look at psu's and everyone reccomended corsair mostly, so i just picked them. For installation im worried that i dont have enough power cables to connect to the gfx card.
Secondly I am unsure how to remove my psu, i get how to remove it, but with all the connections and stuff i dont know where to start really, since my case is a zalman 9 plus, both sides open up, which means that I can do tidy cabling to improve airflow. The people who built it for me used a few extensions since cables wouldnt reach all the way to some places, i think to the single 4 pin power supply to mobo from psu, and 1 or eithe rboth of my sata drives have a extension too, first time im doing this and I want to do it myself so i can learn from it, just wanna start it right, if you could give me any tips, that would be awesome, I will be fine with the gfx ugrading just the psu is a bit confusing because it has a few extra extensions, and im not sure where they all go.
Like nocturatus said you're covered on PCI-E connectors. Regarding all other stuff what I recommend is having the motherboard manual at hand to see where everything goes and do NOT force anything. Where I'm from we have a saying ''the tools are always right''. If it's not fitting then you're doing something wrong or it's not supposed to fit.
It would also help to search on youtube for some videos to give you some reference points.
The PSU is very easy to remove just unplug everything and take out the 4 screws in the back. You could also take pictures/drawings of everything as it is right now so if you screw up (which is not likely) you can put everything back together as it was