thats my confusion was how to engrave, and how to know the detail unless i already had the tubeCorrect you don't need to get the local police to do your fingerprints. You can order the cards off amazon or even get them from the ATF. Some companies will even sell them to you pre-filled out and all you do is ink them up.
For your form 1 you will need details. Length and caliber for sure. Either while you wait, or when you get the form 1 send the tube off to be engraved. OR even do it yourself.
Solvent traps them selves are legal to own. But I waited until my form 1 was approved to buy anything.