No spark and i can only get 5V at the coil.

A resistor is going to drop the voltage. That's what it is there for.
I've got a box of used resistors and they seem to have some variance.
I'm sorry. Did I miss something?

Your ECU could be funky. I had one that was old. It would shut the car off. But I could restart it and drive on.
It finally crapped out and bingo I figured it out.
I'd worry about getting good voltage to the coil at "start" position.
If you have 10.5 to the coil at start that should do it.
You may have other issues that then can be addressed.
All replacement ECUs now have only 4 pins.
Cars used to have a dual resistor and 5 pins.
"They" moved one of those resistors to inside the ECU.
You don't need a dual anymore. The second resistor will be just along for the ride.
Plug and play.
I may get shot, but some people say the resistor isn't necessary at all with electronic ignition. (It was for the points "they" say).
But I still run a single one to be safe on the coil. Why did Chrysler put on in there then?
I don't know.
Snort.
http://www.forabodiesonly.com/mopar/showthread.php?t=318447

I can scan some factory prints in tomorrow if nobody has any links to them.
I'd be surprised if there aren't some in a sticky on here.