Hello, I am wondering what other parts will be needed to convert to single turbo, besides the snail itself.

 

Welcome to the board.

Off the top of my head, pretty much everything one would expect ...
- manifold
- intercooler
- associated piping
- throttle elbow
- downpipe
- wastegate (probably)

Additionally, you will probably be best advised to address the following:
- fuel
- management
- ignition
- cooling

 

Best bet would be a kit from one of the reputable vendors. And then they will be kind of obliged to hold your hand putting together the shopping list for fuel system and ecu as well as be able to point you towards a good tuner and help you with trouble shooting.