stability test in SUR/3SLS

[wolly77]

Hi guys,
I write you because I have a problem. I have estimated a Seemingly unrelated regression (SUR) with 3SLS. The results are good but I have to check the stability of this model. In Eviews there is not a possibility to run CUSUM and CUSUMSQ test or Quandt-Andrews break point test. Any suggestion to test the stability in other ways? Thank you.