i know this thread is old but i thought i would share my experiment experience, i put a sp2 aka 2006 S2000 steering wheel and air bag in my ep3, to make the airbag work electronically i just unbolted the ep3 detonator off the back of the bag, the nuts holding it on are 3 sided so i used parrot jaw pliers, drilled out the mounting holes a tiny bit bigger and bolted it to the back of the S2000 air bag housing. plugged it in and off i went. i assume its safe considering the S2000 air bag is a dual stage bag by design and is the same size as the ep3. i am not responsible for anyone else doing this or swapping a single stage detonator into a dual stage bag but it can easily be done in a way that keeps the bag active and the srs light off.