My best guess is that it would be prudent for Ford, to give the 05 Mustang a year or two, to work any possible kinks out, and start to knock out, one or two year runs of each speciality model. Now the 40th annv. would mean that, a one or two year run of GT350, 500's, on their birthday years. A Mach 1 Special edtion, and of course the Boss version. Now if there are overlapping years, i say pick the best year of each one, and do one version. So lets see someone develop a time line for vehicles for 2006-2010 (i.e 1966-1970)???