Best roll cage for a Dart?

A prebent kit from a reputable manufacture such as S&W and Morrison are a safe bet since the tubing is pretty much guarrenteed to pass inspection with the NHRA but unless your going to run faster 10.0 you wont be inspected. Its the honor system and since its your life your looking to protect its in your best interest to do it right. I agree that custom cages always fit better and you can make it your way. I have done both and have had good results with both obviously the custom one is nicer but the kits are quick and easy for the novice. It sounds like you have most of the tools available and I have a JD Squared manual bender and have found it to be a great tool and I have used it in all kinds of different situations. I try to encourage any of my friends thinking about tackling a new cage to buy a bender and give it a shot. The first cage is more expensive but it will pay for itself in time for sure. One of the other things to remember is that the cheap welded tube is just that and it has a large variance in thickness. Seamless tubing is twice the cost last time I checked but you can put .120 wall tubing in it and the thinnest it will be is .118 per the engineering spec. I built a 12 point cage in a friends 8 second Vega and it passed inspection. If you ad 50-60 feet of cage to your car the extra thickness is just extra weight. I hope this helps.