What should I be seeing for max boost with my setup? The highest I have seen is about 24 lbs.

30-35 psi on the highest level,  24 sound about right on lvl 0 /2/3 depending on tune.

Did you install a boost elbow to hold the waste gate back longer? Stock turbo will come short at about 20 to 25 PSI tops. 

No, did not install any other hardware, boost elbow, etc. Nothing like that in the package with the Quad.

Without a boost elbow it's not going to build more boost.

I was wondering if I needed to add one. 

Get an adjustable boost controller so you can dial in the max boost you want.

You can just plug the hole in the turbo housing where hose comes out to the waste gate actuator to see if it makes a difference. I had plug in mine 1/8npt for years now. With the set up I'm using I haven't had an issue. Just checked my drive pressure against boost and it's 1:1 all the way to 48 psi with wire tap on. I think the waste gate is being pushed open by drive pressure around 45. On level 3 canbus only I can get close to 40 psi.