I believe 5D >6A>j.2A>ad>j.2A>j.C, I think I saw it in one of the Acho videos. 6D seems to be the most rewarding counter now since you get roughly 2.4K and close to 2 stars of meter from the follow up.
I found that the only time Shippu was good in CS was after 2D, since if they bursted you could hold shippu and it would still hit them during recovery. Would have liked it to get higher minimum damage in CS2, but it seems pretty useless now even in the above situation since it will do very little damage if they didn't burst.