I think that will work, but since my does not exsist any more I dont have a way to measure, but I would have to sacrifice the weight and put them back there if I were doing it over. The only other thing I could suggest is if you go with the stock location use screws to attach your windshield. Then you can remove it to get to the servos. You will have to cut a hole in the dash, but it is the only way I know of to get to those screws in the front. It is your bird build it how works best for you Those directions don't come in stone.
Good luck and lets see some pictures. I love to see other peoples projects. It gives me new ideas.
Alan