Hey there -
I'm actually the owner of the crxMPG website,
Go for the swap. It'll help. You can look at metrompg's post on his transmission swap for other data. The d-series guys think they know a lot about how engines work but none of them have actually hooked up an mpguino to measure instantaneous fuel economy, so they're not fully informed.
Best of luck (PS: I'm running an HF tranny on my VX engine in a crx)