TRD shock with 5100's on a non TRD

So I was previously told if i throw my friends TRD coilover in my non TRD regular cab I will probably gain a inch of lift. I was originally going to go with a spacer lift that I still have sitting in my room. But the question is if i take my friends TRD shock and install the billy 5100 am i going to get just 2.5 inches of lift or more because i have the TRD shock that is a little stiffer. Also if i do go with some billy 5100's is their any way I can achieve 3" of lift like adding a half inch spacer plate on tope of the strut or........
Thanks Mike