i would say hot spark and its the cheapest and its the easiest http://www.hot-spark.com/1-3FOR6U1.htm
I would do the Petronix upgrade. I got a ignitor II and flamethrower II combo on e-Bay for about $120 free shipping.
Durapark is the best one in my opinion, Like Jeff I got all the stuff from a junkyard for $10. And if something breaks down you can pick up a replacement part at any parts store, vs having to order one online and waiting days to receive it. Or hoping one of the parts stores has a 6cyl conversion kit in stock, which is almost never.
I don't know! they came out before I was even born. But I've never had a duraspark fail either in the 4 cars that I've run it in. Heck D.S. was so good MSD ripped it off If you google "petronix problems" it does happen quite often, but then again so does any other system that isn't maintained. The blame is often on the product when it should be on the owner.
hot spark is a cheaper one iv run it for about 6 mouths no problems and its only about half the price its about 60 dollars
Too bad you spent 60 bucks on that. for 25 more you could have had a petronix Ignotor I and Flamethrower I with wires. New from reputable dealers on ebay all day every day. But heck if you are ok with cheaper build quality it's your money and your car.
Well I can't claim to have done more than handle one for a few minutes at a car show last year. But my experience tells me it feels cheaply made. The one I was examining had moulding issues that imo could potentially lead to failure of the device from contamination entering the housings. But, then I spent 2 years deciding on what I was doing for ignition upgrade. After spending a lot of time looking up electrical references between parts and my engineering handbook for automotive applications I decided on Ignitor II, Flamethrower II, Ford Racing 9mm wires (I used the HEI distributor cap Scooper - I think - suggests if you search the forum here), and a .042 gap on my plugs. The electrical Specs on the Hot Spark units are a bit inferior and from the pure electrical aspect wouldn't work in that configuration. I'm particularly leery of their coils but I haven't had the opportunity to even see one in person for build quality. Edit- I'm getting about 16 miles per gallon during my daily drive that involves this ( http://maps.google.com/maps?hl=en&s...code_result&ct=title&resnum=2&ved=0CA0Q8gEwAQ ) 5 mile drive over the Portland west hills every day. For comparison my 5.0 efi, manual 5 speed Bronco averages 10mpg on the same road, and it can't climb over the hill at 50-60 like the comet can. The map doesn't show it but according to a bicycling site the average grade is 6.5% and the max grade is 10.78%.