Any froyo kernel should work. I actually dont use custom kernels anymore to overclock. I stick with the default (recommended) kernel and use the milestone overclock app to load the module and set the top desired clockspeed and then use SetCPU to adjust me settings. I suggest you look into it.
all the p3 droid kernels work well with it..... im not running it anymore as its still a loong way from stable but it ran as good as expected with p3 droid.
if i have CM7 and im looking at running a p3 kernel, which section in there should i use? 2.2? 2.1? something else? i have the original droid if it makes a difference it says i have 2.3.3 for my android version but theres no section like that on the site. is there another one i can use?