ST70 or Mark III?

My love of tube amps is rooted in the 60's and 70's when we lugged Mark IIIs and Citation IIs around to power Voice of the Theatre cabs in rock and roll bands. Now 40 years later I'm setting up a small rehearsal room and want to use one of the restored Dynas to run a small PA pushing two Carvin 10" 8 ohm live sound type monitors for practice. Would it be better/more efficient to use the ST 70 to run each monitor at 35w 8 ohms or parallel them out of the 60w Mark III at 4 ohms? Just wondered which would provide best volume, least distortion etc. especially if you start to push them. Seems the Mark III might have more headroom but I don't know. Mainly vocals no instruments.

Thanks to all who helped get these back on line. It's a hoot to fire them up and start using them again. Still have one Mark III giving me trouble replaced caps on board and bias caps, tubes glow kinda sorta but don't get very hot, no sound at all and I am going to replace the quad cap next unless you experts have another suggestion. Hope it's not a tranny. Thanks. IA.

What are the voltages on the non-working Mark III, compared to what's in the factory manual?

As to which one; those monitors are probably quite efficient. The Stereo 70 would be more than enough power, and what's the ACTUAL difference in dB between the Mark III and Stereo 70, anyway? It's small enough that anything pushing the Stereo 70 to clipping would probably clip the Mark III, too.