Locating the running gear and drive train is first. Then frame rails and alignment. Finally the rest of the tube structure. I usualy do a front, center and rear section seperately then join them on the jig when the three sections are nearly complete. This will allow some of the stress from welding to dissapate and not flow through the entire chassis. If you have never built one before, go slow and make sure each and every weld is perfect in every way. You dont wanna bail off into turn 3 at a buck sixty and have a weld break or something to come loose. Also get a copy of the sanctioning bodies rules and insure that you are meeting the minimum diameter and wall thickness requirements from the beginning. Most local inspectors wil be glad to come by your shop and take a look at what your doing so you dont show up at the track and get sent home for something stupid. Have fun and take a look at a program called Bend Tech Pro. Best 200 buck I ever spent for tube chassis and bending software. It has saved me the cost of the software in unwasted tubes that were mis-bent. Hope this helps.
Bob
