My approach is a bit different. I create my border/title in model space - of course at 1 : 1 scale. 99% of my paper size is 24"x36" so the extents of my border are something like (forget exact measurement) 23"x35". 100% of my drawings are printed to Acrobat first so 1/2" (maybe 5/8"?) margins are fine. When I have it just the way I want it, I save it as a TCW file in a special folder I created called XREF_TitleBlocks.
Sometime during my drawing project, I decide to bring in my Title Block. I go to [format] [create external reference] and navigate to my [XREF_TitleBlocks] folder and select the border/title I want. When TC asks for XREF name, type in the same name you gave it as a drawing so you do not become confused later. Click on your blocks palette and it will be there. Drag it out into model space. Create a viewport. Switch to paper space. Insert that viewport, and carefully position it on the proper sized paper.
Some tips: always create these "XREFS" (TC glorified blocks) on layer 0 - all entities. Also, check to make sure there are no other layers in your soon-to-be XREF drawing - only layer 0. Make sure you have nothing in your blocks palette. In short, a clean drawing. Since my drawings (PDF files) end up being sent out and printed on B/W printer(s). I also create everything using a grayscale colors - most of which is 0,0,0.
Hope that helps. Post here if you have trouble. By the way, XREFS in TC are a different animal than XREFS in AC. In TC, they are merely glorified blocks. If you try to apply anything from AC XREFS to TC, you will waste a lot of time and be sorely disappointed.