Anyone know where I can find them? Want to make sure everything is square and within specs before I move forward! Thanks!!

 

Use a right angle edge, and some wax string. You don't need the measurements.

 

What would the wax string be for, forgive I have never done this before?

 

You use the wax string to check for squareness between opposing corners. It's kind of hard to explain, so I'll throw together a quick paint pic to explain it.

 

Quick and sloppy, but hopefully this explains it better. As long as everything is square, you can use the wax string to measure the distance between opposing corners, and the distance should be equal. If the distance is unequal, either something is bent, or you're measuring incorrectly.

 

Got it! I'm definitely a visual learner, thanks bro! I will give this a shot and once I do I will update you with how it went.