Last year when the Wenatchee fires closed part of 97 we took the route that Larry suggested and it's a much flatter route, grade wise. It's about an extra hour or so to get to Wenatchee thru Quincy, but I find it's a more comfortable tow in general because I'm not having to go over all the passes and it's got straighter sections of road, so not so much 'mountain' driving.
Personal preference of course, so unless I just have to be there an hour earlier, I'm sticking with the Quincy route when I go to Wenatchee (we go to Wenatchee Confluence State Park at least once a year.. :) )
Mitch