Older Delta 1400 1500 series too far recessed after changing shower walls

So, I screwed up. Big Time. I demoed my bathroom and paid someone to rebuild it. I bought new shower to go in. The old one was direct to stud. The new one was not, the best way I can describe it is the inside wall of the shower wall is about 1-2 in away from the stud. the end result is when it was all done, I mean the entire bathroom is done, I go to put on the vanity plate and shower handle and it doesn’t fit right. There is a gap because the entire shower mechanism is recessed in the wall too far for the new shower. I can not find anything to extend it. There are extenders, but they are all for other brands or other models of Delta. Its copper so there is no "flex" to it. I can’t just unscrew and pull the mechanism forward, at least not enough. Any ideas?