what's the easiest way to reconform a project shot in HD that was cut in the DS in an SD project and the client wants an HD version of it?  

Same framerate for both? If so, take the SD sequence, and save a copy. Create a new HD sequence with the appropriate scaling for the presets drop in the SD cut and recapture the media from the HD source. If different framerates, good luck.

Since DS does not support SD at 23.97 or 24, I guess this HD material is in a compatible 59.94 frame rate, and so Michael suggestion will work.

In the HD sequence, make sure to go under File > Sequence Preferences and set the Conversion Mode so the effects presets and media adjust to be proper scaling or the loaded SD sequence may end up wrong in the HD frame.  You might want to experiment a bit with very small sequences first hand, but you should figure out the proper recipe quickly.

I was thinking he may have used the decks downconvert for the SD source So the HD source could be 23.98 and the SD source 29.97.

If this is the case, you can take your SD cut and load it into the EDL tool(save it somewhere you can find it), then process the 29.97 edl to 23.98 through the EDL Processor (look under tools). The difficulty lies in rebuilding any effects and composites. You would need to carefully save effects presets to a toolbar or bin from the SD cut for use in the HD cut.

I guess if Steve does not reply then we'll never know...

frame rates matched so that was not an issue. Ended up importing SD sequence into HD timeline,

purged media from sequence and recaptured at the proper size- programs were short so it went pretty quickly.

thanks for the input always nice to have several ways of attacking client curveballs.