Yes, bhodginsCCI, that's exactly what you need to do!

But FYI, let me add a few other details.  When teaching this topic in the Intermediate Depreciation class (offered through Sage U), we have enumerated the process into the following 3 steps:

1. Navigate into the detailed view of the disposed asset.
2. Use the command Delete Last Transaction.
3. If required, calculate depreciation to your desired date.  (The program always calculates depreciation to the disposal date.  Therefore, if your disposal occurred some months ago, you may need to advance depreciation in order to catch the depreciation expense since it was disposed.)

If you have already posted the gains and/or losses to other financial documents, you may want to print the Transactions tab before you unwind the disposal.  This will give you a handy reference to have if you must back out figures that you've already posted because once you have cleared the disposal, those gains and losses will be erased.