Ok, I did it. I'm pleased. I like my fancy slate frames...they work great. But it is a nuisance to lace them in. Then you have to cut the lacings, reroll the ends, and repeg it, and then relace it. Hate that last step!
Here are the steps:
I made a bit of a template.
I sewed casing strips to the top and bottom of my fabric and marked it from the template.
Sewed the embroidery fabric to the side slate pieces.
Rolled up up and put in the top and bottom sliding frame pieces. Then I stretched them out and pegged it, to make it taught.
This works well, but you really need it stretched vertically as well...which is where one usually laces it, like they did with the Plimoth project, you can see the lacing on the side, here:
Too frustrating, given that I'll be moving it a few times, and I don't want to leave it under tension, because of the 3-D ribbon.
So I threaded dowels through my casings, then used binder clips, tied to string, and hood string clips to hold the strings under tension! It's quick and easy to move those, and tighten them back up!
See? Much easier! I feel clever! Let's see how it works....on to the embroidery!