It depends on the jig. The chord of the 7?s wing is wider than the 9?s, so the jig might have to be a little higher to accommodate the extra width. The 9's wing is longer than the 7?s wing, so you have to be able to move the two jigs closer together to accommodate the 7?s shorter spar.
Since you?re in Claremont, you might check with EAA 448 at Cable to see if they have a jig you can use. I used one of the chapter?s jigs to build my 9?s wings. The same jig had previously been used to build the wings for a 6.