whoa
if mules are still too dark and not clear enough, the next step would be riff raffs
SGs can be a pain in the ass to match pickups
also, the tiny terror, as most el84 small amps, tends to mud the mids up under heavy gain
there's the jet city jca20, which I find to be a little more open sounding than the tiny terror (and costs half of an orange)
the riff raffs will help, but won't solve this
a bigger 40w-60w amp with 6l6/el34 tubes and a brighter voicing wouldn't require new pickups, unless your SG is REALLY dark sounding