'69 Barracudas and '66 Darts are two different animals as far as engine mounting goes. You'll get more help by starting your own threads instead of saddling on someone else's, one in the Early A Body forum for your '66 and one in the Small Block Mopar forum for the '69.
But first, use SEARCH in each of those forums, as these questions have been asked hundreds of times and your answers/solutions are already well documented- as a matter of fact, the answer to the '66 is above.
