Miserlou
I accept under constant conditions there is a good correlation between CHT and EGT but while EGT gives you instant response to leaning, CHT has a big time lag on it, and anyway is hugely affected by the airflow speed.
To lean by CHT, you would need to be in stabilised cruise, or a stabilised cruise climb/descent.
If one is going to spend money on a CHT gauge, one might as well spend money on an EGT gauge. Or get an EDM700 and do it properly
