Why would you run without a thermostat? Is there something specific you are trying to do with the car, or is this just in general. If it is just in general, then I say BAD idea...
if you do run without a thermostat you will get shitty gas mileage, because the computer is set up to operate with a certain temp. which will affect the air fuel ratio.
No. 94-99 are completely different. 00-05, you may be able to put an SRT4 hood on a neon, but you may find engine clearance issues with a regular Neon hood on an SRT4.