✓ Accepted answer
You will need to either use a 'Weld', a 'Motor6D', or the new 'WeldConstraint' and position the model onto the UpperTorso, and then set the Part0 to the UpperTorso, and the Part1 to the base part of the model. All the model parts need to be unanchored and welded, you can preset this by searching 'QPerfectWeld' or "QWeld' in the free model section and putting it into the model. Then run the game, take a copy of the model, and stop and repaste the copy in the workspace or whatever storage you want to use. Use the welded model to attach to the player. If this still doesn't work you should look more into Roblox welds and how they work so you have a better understanding of how to solve this.
2 comments
You will have to make your own weld script.
Yeah I've tried but it just disappears?? If you want I can link you my script and you can possibly find where the error is