Problem with that is there's a dog-leg in the sides when you do it that way. I fought it out this afternoon and got it to work. I made a copy of the crown pattern and counted down 7 holes (out of 20). I put the old pattern on the new one at that point, making sure the overlap on each side was equal (1/2 inch in this case on each side.) Then I marked the new top of the pattern. All I had to do then was link the top line with the bottom one and transfer the holes from the old pattern. Fits just fine.
Caveat: Those measurements are for the large Aristocrat, medium and small will have less overlap, I think.
If I do it again I'll go with 10 holes rather than 12. There's not enough difference between a full-scale crown and this shorter one for me. Again, your mileage may vary.