building a new frame

I was wondering what the hardest part is on building a new frame? Im probally going to build a new frame for my 63 impala and get rid of the x frame and was just wondering about some of the things i should look for? Is the measurements the most important? This is going to be my first full frame build also so any help would be appreciated. Thanks

why in the world would you get rid of the x frame? thats signature impala....

Yeah i wouldnt get rid of it, But i would box the rear quarter of it (under the trunk, it has a TON of flex that causes cracks on the b pillars) And also just brace the X by running bars from front to rear along the jams. Thats what we did on our 63SS. It now handles a hell of a lot better and is more constant on launches.

dont ditch the x frame!! those stress cracks are common on the 62-64 impalas, the rotted body mounts are usually the cause