If the name shows up in the browse returns, you can click on that image and open it in the Transcription window. From there you can open the LINK andit will show the image number in blue (hard to read) letters.
BUT, if you just want to link the older one with your new photos, the easiest way is to transcribe your photos so that the entry is identical to the info in the previous photos. Save and then click on the person you just transcribed and open it in a new window. If they are identical you will see the MERGE arrow in the upper right. Click on that and check that the merge of the two sets is correct. After you have done the merge, all the images should appear together.
I usually reload the transcription page just to make sure it did merge properly, especially if there are more than one person in the records.