[NTG-context] How to make a block of text narrower?

I need to make a section of text in my document narrower, about .6666\textwidth. Basically the text has normal alignment and everything, just instead of filling \textwidth, its compressed so there is a larger white space to the right. I've tried dozens of things, but cannot get a good solution, every solution has strange other effects. The best thing that has worked so far is \setuplayout[width=3in] But the problem with this solution is then I cannot get it to return to the original settings afterward. --Joel