The harness IS the easy way and the safest way, it avoids damaging the factory wiring. Well worth the 10-15 bucks. Twisting wire together and electrical taping it is ghetto bullshit, it'll come apart and short out, you could fry your head unit. Spend a couple bucks on some butt connectors.
I'm 99% sure the harnesses are the same. The harness in my 95 Integra and my 98 Civic were the same. In fact, just yesterday I put the Alpine that was in my Civic into the Teg. Really easy swap over.