Lifting cab

[gopokes]

Hey guys I need a little help. I am getting ready to shorten my longbed down to a shortbed and want to do it without taking the cab all the way off. I am using my truck as a dd right now and am affraid if I take the cab all the way off I will be going down a bad path... I already told my wife this wouldn't take up the garage for too long. Does anyone know how high i can lift the cab off of the frame without actually removing it completely?? I think if i can get it up a few inches it will give me enough room to cut and reweld the frame. I will be reinforcing it like glock35ipsc did on his build. I have read that faq like 20 times. My brother will be helping me with the welding and says it shouldn't be a problem (he's been welding for over 20 yrs). I just wanted to get some more input before jumping in with both feet. Thanks!