4,1 Dual / Single CPU Tray interchangability?

I have a single cpu 4,1 (flashed to 5,1) that I have upgraded to a 3.46 cpu, but unfortunately I had a case issue with it and need to replace the case.

I have located near me a DUAL CPU 4,1 (again flashed to 5,1) that otherwise would make a suitable donor. What I would like to do is swap my entire single CPU tray into the new dual CPU system.

I know there are issues between 4,1/5,1 models, but are these issues within the same model?

Thanks!