Tranny shifts early

All of them shift early, especially behind power. 3rd by 20mph is normal. This is why I have a ratchet shifter for my 42RH. Unless you want to pull it and mess with the govenor weights. (good luck)

Set-up the lokar so it is at FULL pull with 1/16" cable gap at the clip for the linkage at WOT and walk away. I have a spring to return the arm on the transmission for fun.