Small Bolt Pattern Wheel Adapters???
Ohh....boy. I'm not a big fan of wheel adapters. Just one more thing to go wrong. If money is an issue, have a set of 4.5" bolt pattern rims drilled for the 4" pattern. It's still a cheese-ball modification, but a bit more safe. I've seen rims re-drilled for the street that worked fine. I wouldn't put any serious horsepower to them, but for the street it should be OK.
If your hell-bent on wheel adapters, IMHO,make sure you torque them on with some mild thread-lock. And check them from time to time.