Placement of the PSU is this important for cooling ?

Placement of the PSU is this important for cooling ?

I have the PSU in my case right above the CPU, even though their is
space above it for it, just have to cut a hole and add a bracket to
install it their, the cables are long enough to plug everything in and
all.

I just read somewhere AMD site the best place for the PSu is at the
Top of the rear of the case this true if i move it should i get better
cooling.

With the PSu at the top of my case i can place my 2 80mm next to my
CPu and install a duct so all the hot air is drawn out of the PC
without entering the case.

Also duct cool air to the CPu via the side fan i have, this should
cool the CPu down alot and keep the case cool as well.

I could also duct the hot air away by cutting a hole in the back of my
desk to duct the air away from my cpu, insteadof it just building up
under my desk, think thats a good idea ?

Any help.

Thanks.