Originally Posted by
zzyzx_xyzzy
it'd still be awkward to route the cable from the barcon around a clamp unless it's a thin steel strap type clamp. you could get regular flatbar type levers with a 24mm clamp from velo orange and run them in a non-reversed position... or mount your shifters on some paul thumbies behind regular inverse levers?
This post made me think of something else the OP should consider. Most (all?) reverse/TT levers are meant to be mounted on a curve (the end of bullhorns/TT bars curve up), and therefore the levers do not stick as far out as compared to a lever meant to be mounted on a flat section of bars. Using reverse brake levers on a flat section could lead to the lever hitting the bar before full braking is realized.
If you're set on mounting brake levers at the ends of your mustache bars, then using interrupter levers like zzyzx_xyzzy suggests, IMO, would work best. A couple issues would be the routing of the shifter housing and having to wrap tape on both sides of the brake lever.