The problem is once you make a weapon into a SBR or SBS, it has to be stamped with markings and kept as is, it can't be modified back to a non-ClassIII weapon.
Your best bet is to decide what you want it to be, submit the form application, and then do the modification properly and live with what you have made and sell it if you decide it's not what you want anymore.
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Colt M1911, AR-15 | S&W Model 19, Model 27| SIG P238 | Berreta 85B Cheetah | Ruger Blackhawk .357MAG, Bearcat "Shopkeeper" .22LR| Remington Marine Magnum SP 12GA., Model 700 SPS .223
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