HELP!!! Wheels & Tires

Hey!
About a year and a half ago, I listened to my instinct and bought a 1970 Plymouth Duster. Not knowing much about it, I totally underestimated what a project it truly is.
I again ran into a problem. My Duster is a 225 slant 6. With that said, I have been very unlucky. My bolt pattern is in the way. (5 - 4")... I've been given different solutions and I don't know which one would be best. 1.) Front drums to disc conversion and drill rear... 2.) Find an adapter... 3.) Find barracuda plating part with the more popular pattern 5 - 4 1/2.....WHAT DO I DO???