So, I drive a bit (24,000 miles since November 19th) and I have been experiencing mid and lower back pain. I read on a few places different seat "mods" and looking at things like the Corebeau lumbar support, Sparco lumbar pillow and Kidney Supports, but to have everything I wanted was going to be over $50.
Side note, I have a friend who has a 13 EVO and if you have ever sat in those seats, the bolstering is amazing, which made me want to put it in my seats.
I ended up going to Walmart and buying some foam for $6 and I put 1" of lower back support, 2" of mid back support (keep in mind when you sit in it the foam compresses) and while I was there I added 1" of bolstering to each side. I have only driven it about 10 miles since I did it (I did it an hour ago), but the difference is amazing, especially the side bolstering because now it rests on each side of my ribs and fits like a glove.
Here are some pics:
Foam Cut (Bolstering):
Foam added behind the metal in the back of the seat:
Stock passenger seat for "before shot":
After all said and done. It is hard to see, but well worth 6 whole dollars: