Rat's connector is the best bet it you like what you got, just FYI I think you need the connector for a autometer tach also...
As far as connectivity, I think speedhut.com has the only gauges that connects to coil on plug or the factory output without a connector... some guys online seem to have figured it out easily, some guys have had trouble.
I like speedhut gauges because they are totally customizable without a cost increase. (and their relatively cheap) Seems like a bunch of members here have bought them, but I dont know who has them in use yet. youtube has some videos of them in use. I ordered a whole set with a GPS speedo... So we shall see.
JOE