There have been many cases where dealers and their sales people were very hard on these cars. Blown engines, clutches , transmissions The tails and side covers were very fragile compared to iron versions. Ive had customers that broke out side covers and tail shafts just by power shifting. Try to find a 4 speed Hertz 66 that #1 has the original transmission #2 has one that hasn't been welded . We've probably been involved in the restoration of close to 100 of these all aluminum transmissions and Im guessing Ive weld repaired over 30%. Its always a treat to get one that the alloy case and tail or in good shape. The one trans that was a head scratcher was the one that was in 6S001. The case and tail were near perfect castings but the inside was just trashed. we had to replace virtually all the parts in side.