Originally Posted by Haggar
Yup. In fact, on a lot of 6.0/4L80e combos had that spacer as an OEM piece, because they didn't make a longer snout 4L80e.
Make sure you get the longer crankshaft bolts as well to go with it.
Torque converter bolts.... The flexplate has to stay where it is or the starter won't line up correctly. Most of the adapters I have seen don't use any of the crankshaft bolts to fasten it but if the one she gets does then those are needed too.
If you do use longer crankshaft bolts make sure they aren't too long or you'll lock up the engine by bottoming out on the bearing cap.