How do I make consistent landings from the (instrument-less) backseat? When flying the Super Decathlon from the backseat, I can see the manifold pressure (top left corner of the panel) and G-meter (top right corner), and that's it.  This (along with the fact that the guy in the front seat blocks the view of the runway centerline) makes it difficult to get good consistency in landings.

I know that in if your airspeed indicator fails for some reason you can simply keep a little throttle in, fly until ground effect, and then bleed off whatever speed remains, but that's inconsistent and ugly.  I'm talking about being able to hit any arbitrary point on the runway ten times in a row.  I would call that impossible without at least an airspeed indicator, but older, wiser pilots have been doing it for years.

How do I make consistent landings from the (instrument-less) backseat?
Since nobody else has posted an answer, I follow Dan's suggestion and copy my comment here. Unanswered questions make this site look bad.

Practice, practice, practice. It's for a reason that the pilots who fly consistently good landings are the older ones. And remember where the horizon is in reference to the airframe and how the engine sounds. At approach speed (= at high angle of attack) the aircraft will show large attitude changes for small airspeed changes. Remember how high you are at conspicuous points along the approach, don't be shy to look sideways for this. And keeping a little throttle makes better landings, so don't feel negative about this.