Another alternative is that some Chinese and no doubt US suppliers (at a much higher price) are offering a new case that is preassembled and is fitted with almost all of the required flex cables (the one I got didn’t have a bluetooth cable so I used the old one), Taptic Engine, speaker, Lightning Port and all the switches. You need to transfer the logic board from your old phone obviously and both front and rear facing cameras camera’s. The one I got from China cost me about $67 and it works fine.
Tip for the Day : Google is your Friend. Short answer is Yes. Do a google search and you will find heaps of them on E-Bay and Amazon, but with all things OEM you have to take the risk that some will be great and others will be complete crap. Although I have not used high capacity batteries I have used OEM batteries from China and my experience has been just that, some were good and some not so good. Good Luck :-)
What do you mean when you say “put in logic module” ? you mean you replaced the original logic board with another known working logic board ? And if you have access to a multimeter you can measure it to see if its ok or not