I've sent over a dozen 70 Chevelle clusters to Gary at H&H auto with excellent results.He will even go the extra mile and not silk screen or polish up an original if it's not really necessary.He understands the importance of orginal authentic appearance being first and foremost,and if that's not possible,he'll restore it to better then new.
He's also known as the Tachman.
http://www.tachman.com/gm.htm