We need to open an direct interface to link the two TARDIS' together so that when I make the modifications here in yours, then Handy's will also get them. His TARDIS is going to be extremely touchy about having anything to do with me, far more so than yours because it's closer in the timeline to when I created my Paradox Machine. It's going to be your job to keep them both calm while I work.
I'll need a full set of tools, including a screwdriver, and access to the data core. When I had the TARDIS onboard the Valiant, I transferred a complete set of the schematics to her in case I needed quick access to them. There should be an encrypted subfile hidden deep in the database.
You do realize this is going to take a couple of days though.