Stop an auto from shifting?

[000ADRush]

Hey guys I own am s13. It's an auto and right now I cant afford a tranny swap. Is there a way to stop my car from shifting ? I was thinking a bee r but wasn't sure because of it being an auto. ( obviously drifting purposes) I also have an e39 5 series in which I want to do the same thing

Ps I'm sure it's on here some where but I don't know what to search regarding this matter