4 pin ECU with 5 pin harness

[tricky lugnuts]

Getting set to order some electronic ignition parts for winter upgrades on the 1971 Charger and want to clarify one thing before I spend all my hard-earned money:

* I presently have a 5-pin ECU, some Made in Malaysia Auto Zone piece from years ago, and a 5-pin wiring harness. Can I just bolt on a new 4-pin ECU and plug that into the 5-pin wiring harness and continue on with life as usual, keeping my 4-prong dual ballast resistor?

I've "read on the Internet" this was true, but just want to try and make sure. Are there any downsides to doing that?

Also, what's the preferred ECU for a mostly street-driven vehicle? I've read about lots of Mopar orange box failures on this site and others . . . But, aside from a high-cost MSD set up, is the orange box still the best way to go?

Would I see any advantage to running the chrome box, even if my engine (a 440) will never see upward of 6,000 RPM, which the orange box is rated to?

Assuming the 4-pin to 5-pin wiring will work, I plan to order the ECU, an Accel super stock ignition coil, a "1970 and newer" voltage regulator, and a couple dual ballast resistors.

Thanks for the feedback!

[John_Kunkel]

If you're going to buy new ballast resistors anyway why stay with the dual ballast? Buy single ballasts and eliminate the 5th wire that goes to the ECU since it's going to be a 4-pin ECU.

[tricky lugnuts]

OK -

So the 4 pin ECU will work with a 5 pin harness - then just cut out the fifth wire in the harness (red and green, I think), switch to a single ballast, wire the brown wire on one side of the ballast and the blue wire on the other . . . and everything should be good to go?

[Nacho-RT74]

you just need not to use the green traced wire arriving to ballast ( cut &/or hide down the tape ), and eliminate the blue wire jumper... done.

no need to cut the green traced red wire at ECU plug