Years ago I did the Joe Curcio mod to a ST70.

There are all sorts of kits to rebuild your MKIII. You can also just rebuild the original circuit with stock parts as well.

I owned a bunch of Dyna stuff, and I used the ST70 with a rebuilt ST35 and a modified pair of Heathkit tube electronic crossovers to bi-amp my Altecs. I also had a pair of MKVI monoblocks, the 120 watt monsters made in 1976.

With the MKIII, basic mods include replacing the tube rectifier with diodes, and cramming in as much filtration as possible. This will enhance headroom and tighten up the bass.

So what have you done already? Lets see those pix!

"Tyranny, like hell, is not easily conquered… What we obtain too cheap, we esteem too lightly: it is dearness only that gives every thing its value. Heaven knows how to put a proper price upon its goods; and it would be strange indeed if so celestial an article as FREEDOM should not be highly rated."
-Thomas Paine