i guess this is kinda old but ima bring it back alive to those who is asking about the horn.. for the horn u must tap into the horn wire with is with the connector underneath the kickpanel somewhere in there with the 2 cruise wire also. u must run the wire to underneath the copper part of the hub and must touch the back of the copper with like a metal tab or something. then your horn should work... i did this project when nrg first came out and was able to wire everything except the cruise because i wasn't able to find the right push buttons.. it's pretty cool! here's mine
for the srs light.. i know for a fact you can reset it.. or just unplug the plug from the cluster then wallah! dissapear!! youtube the video how to reset srs.. a guy there show how to...