7 1/4" to 8 3/4" rear end swap advice

cosgig said
, there are 2 different A body 8 3/4” housings, a 66-69 and a 70 and later

buy the flex line for the year of the housing and the car.

If you have the "up to 69" housing buy the hose for a 67/68 dart with 8 3/4

If you have the "70 up" housing, get a 71/72 dart with 8 3/4 hose.