I think you will be fine using the Companion Angle ruler. You might want
to make a test with some scraps to make sure it works before you cut
your good fabric.

This is a Youtube video by Cozy Quilts. Maybe you can tell from this if one of your rulers will work. https://www.youtube.com/watch?v=3BLCz8Ee320

Thanks everyone, I ordered the pattern and I also watched the MSC tutorial. I will use my square ruler.

Good girl. Our old square rulers can do so many things. Have fun!!

I have the Strip Ruler and use it to square up hsts without opening the hst. It's a versatile ruler. I forgot it was in my save for later list at Walmart and I got a notice last Friday the price had dropped to $5.99. That price was good for a few hours.