rumblestrip

Picked up this pair of AR-12's the other day for a song. Almost passed them by because they have been painted brown over the original walnut veneer so that they looked like cheapies. Otherwise in excellent shape and complete except for the rotted-away foam surrounds and dispersion rings on the tweeters. Got them home only to find that one of the midranges is dead. Took them both out to measure the resistance on the one still working. It metered out at 3.6 ohms. Does this mean the midranges were originally 4 ohm speakers or could they be 6 or even 8? Does anyone have any experience with these so that they would know for sure? If so please let me know. There is very little about this model online. Also, is it worth having just the one recoiled, or should I do both?