The only source I'm aware of is the "Mustang Monthly" magazine. In their May and June 2001 issues (2-part series) they had a feature which showed the exact locations for all emblems 65-68. Can't remember if 64 was included or if there's a difference in placement from 64-65. Was a tremendous help especially in lining up my trunk lid letters since I bought a new repro trunk lid and decided to use stick-on letters instead of attempting to drill 14 perfectly aligned holes for the barrel nuts (repro lids don't come pre-drilled for the letters). Unfortunately, I didn't save my copies of the magazine. Try their website at
www.mustangmonthly.com. I know you can purchase back issues for $4.99.