Look into Fortron or Sparkle for your PSu needs, they are really nice, and worth the extra bucks you spend
. Get some good 120's and you should be all good. Till you get further into cooling your pc.
If you do a search on fans in this forum you will find there is a variety of fans you can use. Are you going silent or all out for air.. some fans can be quite annoying (unless you 7v mod them). One rule of thumb is in from the bottom and out the top. You could even put a blowhole in the top of the case, that would create more airflow. On the note of airflow, have you done any wire manegment? Sleeving not only looks neat, it helps with airflow. But if you were to.. lets say tuck some extra wires between the mobo tray and the side panel. It would clean the inside up alot and get them pesky air resticting wires outtas the airflow. Tucking wires into a unused drive bay helps too. Rounded cables are nice wy also, or just mod the ribbons, even just moving (attaching) the cables to the side of tray. Try to get as much non-obstructed air going through the case as possible. I got like 5°C drop in case temp cleaning up my airflow. Another way to drop temps(CPU) is lapping the HS and using AS5 you can squeeze another 10°C on the (est.) outta it. On my stock cooler It was hella nice to see an imediate 4°C (went from 50°C - 40° after AS5 set in period) drop after the lap. One mod I have also done is put a fan on the floor of the case. Oh can't forget that I have a fan right over the CPU cooler blowing air directly onto the Gigabyte cooler. Right now My temps, idle sit at around CPU-36°C Case- 36°C. My case temps are lil skewed due to air washing over the mobo sensor. I am still moving stuff around as I feel frisky to solve this issue. Every PC has different needs and not one way will cure the heat issue. So be prepared to adjust your airflow to accomidate, if needed.
But there is lots of ways to drop temps and get that side panel back on.
BTW what case are you using? That helps, maybe someone who has the same case will notice and offer input.
Edit: Cut out them fan grids out, that is a common way to get them fans more air, and not as noisey.