It will take. Here's one of the first dyes I did with just shoving a disc in a bag overnight
I did the black that way and the colors by hand after. The big tupperware container to the right of the rit packages was actually where i stored my bags of dye and let them sit overnight.
Im not sure that what you're gonna do will work tho. If you're spraying it onto the disc, and plan on keeping it on the disc overnight, my logic tells me that it's going to all run off the sides. The dye I did with the bag method was when it was completely soaked in rit overnight.
The only way I can see this maybe working is if you got the outline of the hand, colored what you didn't want to dye with a wax crayon (I did several dyes like this and it works.. Not great, but it works) and let that sit overnight. But then again maybe I'm just not understanding what you're planning on doing
Good luck with it