gtx580 upgrade questions

Hi all thinking about upgrading to atleast a gtx970 as my evga sc gtx580 has served me well for the last nearly 5 years now.

Just have a few questions before i get this for christmas as my rig is mainly a fsx pc

I know there wont be much of a performance boost but there a few games that coming out i would like to take advantage of.

The main reason for the upgrade is the 580 runs really hot and the noise level.

What im worried about is i have just got fsx running as near enough perfect and the last thing i want to do is sit and have to play about with the cfg files or settings in fsx

So what is the best procedure for installing a new card with fsx.

Whats the best driver software removal tool so it can be installed fresh and also do i need to change anything in fsx like remove the gtx580 line from the cfg and put in a line for the gtx 970 / 980

also will the asus strix card fit in my antec 1200 surely that will be fine.

and also what card would you go for as i have always went with the best card avaliable but money and the amount of time i can now use my pc is limited compared to when i bought it due to work etc so im looking for the most bang per buck.

my pc specs

antec1200

i5 2500k @ 4.5ghz

noctua nh d 14 cooler

gigabyte ud4 b3 motherboard

corsair hx1000w modular psu

Evga gtx580 sc 797mhz

8gb corsair vengeance 1600mhz

asus vk266h monitor 1920x1200

Thanks