First of all, wanna tell you guys that you've done a great job all around on this....As simple as AC-DC's sound is, it's really hard to nail, but you guys did a great job!!!! Everything sounds great, & the vocals really surprised me, as that's one thing that I really struggle with myself, always have, & probably always will....Super job guys!!!!
Now, onto the nits I have....(sorry...LOL)...
The guitars are in the ballpark, but c'mon Greg, I've heard you pretty much nail any tone you want, you've got any Marshall tone one could want....To me, the guitars sound just a little undergained, & lack the bite that they need....Maybe dial in a little more top end??? I dunno, while they do sound really good (I couldn't even get close myself...), they need the "bite" to really cut through...Still, they sound great man, my hat's off to ya, as usual....
The bass (as mentioned) is a little un-definded...maybe it's where I'm not using my usual 'phones/setup to listen, but the bass could used a little more mid-high mid range boost.....Still, again, I couldn't do this....
Drums sound killer, but they've got just a little too much 'verb or something, like the guitars, the drums need to sound just a little more raw....
Of course, this is to try & nail their sound, which would be impossible for me to do, but you guys have done a great job putting your own spin on a classic song, & again my hat's off to both of you....Great job!!!!!