If you truly want to run nitrous safely then you wil want to add these to your kit:

RPM window switch
Lean cutoff switch
Purge
Bottle warmer

You can find used kits cheap. Around here they are in the $200-$300 range for a full kit.

You can use a TB spacer to tap for the nozzle. Or if you are running an external MAF you could place the nozzle after the MAF in the air intake.