PSD's haven't broken 800 hp yet on the HEUI injection system, whether it be a 7.3 or a 6.0.
High 700's is obtainable on NOS, and high 600's on fuel alone. Both of those best numbers come from a 7.3. The 7.3 is still the quickest/fastest powerstroke in a fullsize pickup.
Dockboy weighed around 7600lbs and had the following that I know of...
2000 F250 ext cab long bed 4x4 11.88 - best 1/4mile time.
AFE intake
Modded H2E turbo
3.5" dp to stacks
DP Tuned
Custom Rods
BTS tranny
BTS big oil
Custom fuel system
Studs, fireringed
big shot of NOS
530 7hole injectors
Stock intercooler I do believe!!!