I labeled each item so we could quickly identify each. Below the photo I've gone through the hardware really quickly and described the ones I could think of off the top of my head. I've left the ones I couldn't recognize immediately blank. I'll get back to you on those.
A: 3/8 split washers - Used with B, L and H to hold down the back of the seat.
B: 3/8 flat washers - See above. Also used in many places on the front suspension, rear strut mounts and more.
C: Toe link rack washers - Used with Q to hold the toe link rack at the rear of the subframe. I think using your stock bolts is okay.
D:
E:
F: M8 BHCS - Used to tighten the steering shaft universal joints around the splined shafts top and bottom. I think using your stock bolts is okay.
G:
H: 3/8 carriage bolts - see A and B. Rear seat mounts (your second seat should be arriving this week if Corbeau ships soon)
I:
J: 1/4 flat washer - used all over the place: shifter bellcrank (under the head of the bolt and nut), brake line clamps on front control arms (you used those cool ATV clamps instead), BCM mounts, and a lot more
K:
L: 3/8 nut - See A, B and H.
M: 1/4-20 nylok nut - Would've been used on the brake line clamps on the front control arms
N: 5/8 safety washers - These are very important. They should go above and below all 4 of the big rod ends (2 washers per rod end).
O:
P: 10-32 SHCS - brake res adapter bolt
Q: Toe link rack bolts
R: 1/4-20 nylok jam nut - I think these were for the floor support strap under the pan
S: Rubber isolated radiator studs - these should go between the top of the radiator and frame
T: 10-32 nylok nut - brake res adapter, brake mc adapter hold down and tail light nuts
U: M14 HHCS - These hold the top loop of the stock seat belt. You won't use them since you are running harnesses instead.