First, I'm back home after three weeks of Katrina wandering, and it feels great.
Second, there are DOT requirements, but you've got to check your local laws and how they are enforced. This varies quite a bit. Where I live integrated signals will get you a ticket promptly even if you leave the standard turn signals in place and functioning (alters function of brake light and taillight). The lights have to stay where the manufacturer put them. You can change the lights themselves, but the location can't be changed.
Other problems you would have is that you couldn't get a brake tag = can't get insurance = they take your plate away (or if you're caught riding without insurance the bike would be seized and you would be in for a $500 fine).
On the other hand you're required to have a front fender, but this is almost never enforced unless in conjunction with another infraction. Check locally and make sure you won't have legal problems before you do the mod.