Never heard of someone switching a neg ground system to pos ground. Are you sure it's not a GMC that you think is a Chevy? GMC's had pos ground during early eras.

Read this for change over advice regardless of what you have.
http://www.inliners.org/tech/12v.html


Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn