It’s probably worth moving your build questions to a new thread since you are definitely gonna have some issues outfitting that instrument with both a headpieces and a bridge.
First of all, you cannot use an “on top”headpiece like the nice one Nova provides (as being recommended by Snert) or many of the others since they require part of the headpiece to be partially left in tact to mount to the top. You will have to use one that bolts to the end of the neck since you have no headstock at all.
The other issue you’re gonna have is with that body, and where the current bridge is mounted if that is to scale which I’m assuming it is, you are going to have to route into the body to leave room for the tuners so you could actually use them.
You may even consider altering the back end of the body to open it up quite a bit so you could use a headless bridge.
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Again, this should be on its own thread.