727 slip yoke on 7 1/4 driveshaft

or since it's just a 340, with an automatic,
forget those 1350s and just run whatever you got,
If your 727 yoke has a 7290 on it and everything else is 7260, just get an adapter U-joint.
If you don't have any 727 yoke at all, except the 1350, well sell it and just get whatever 727 yoke you can find , you can get the adapter at any jobber. On the 7260s tho, I highly recommend a driveshaft loop, for that one time you forget.