I am working with a very long pre-existing PowerPoint presentation (several hundred slides).  

I need to leave the Master title text box (as set up in the master slide) intact as far as location and content, but create a different text box as the Master title text box.  

What I would like to do is insert a different Master title text box in the master slide, put what I want in it in every slide and change the existing Master title text boxes to regular text boxes.  I do not see where there are any property settings to do this.

I tried to go to the master slide and create a duplicate of the Master title text box and then try to convert the original one to a regular text box.  I first just tried to create a duplicate of the Master Title text box, and I got a duplicate text box, but PowerPoint ignores it as a Master title text box.

Anyone know how I can create a new Master title text box in the master slide and convert the old Master title text box to a normal text box?

Ultimately what I am after is to use the fewest possible characters in the master title text box for use in hyperlinking so that I do not run out of memory for the hyperlinks.  That is, instead of 10 - 30 slide titles, I can cut them all to just 3 or 4 characters, freeing up a lot of memory.  I would like to avoid having to copy the text from the title slide to a new text box, align the new text box, and then enter the smaller title (for use in hyperlinking)in the existing master title text boxes.  And then making this text white (to be invisible) and moving it out of the way.  That is a lot of steps to go through 230 times (for every slide, that is).  

And yes, I know that another option is to break up the presentation into pieces (4, for example) and then hyperlink each of them to a small master presentation, thus allowing maybe 4 times the memory for hyperlinks since the hyperlinks would now be spread over 4 sub-presentations.  But that also involves a complicated structure that many of the users may have difficulty coping with.