MSD mechanical dizzy
Don @ FBO sells 10* and 14* advance bushing for MSD distributors exactly for this reason...because MSD doesnt supply them. Give him a buzz, he may have a 12*...not sure.
www.4secondsflat.com
Here's a link to Don's tech page regarding this very issue...good luck:
http://www.4secondsflat.com/MSD%20Distributor%20Tuning.htm
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