Lift kit questions

So, I'm new here, I recently bought an 06 2720SL. It has the 14" wheels and it is time to replace the tires. So, I called the factory, they're out of lift kits right now. Do you know of other sources? Can I get some 2 by 2 stock and drill holes myself, then get a certain grade of bolt? What thickness is the sidewall of the factory 2 by 2 stock? What size bolts do I need, and what grade? I saw there is a currently a tack weld holding the axle in place on the frame. Did you guys just grind off the old weld? Was it fairly easy and non-destructive to the frame? Did you put new welds in place once the lift was installed?

Maybe you can point me to some instructions on how to put the lift kit in. It seems like a project that can be done by myself, I'd just like to avoid any problems, both during the install and then when traveling down the road. Thanks for the help.