Root CWMod, root problem


Okay peeps, I'm aware that we'll get signature verification issues with Froyo unless we revert to recovery 2e. Thing is, I already have 2e, being that I'm on Eclair. So...why can't I apply I can't install CWMod via Rom manager, because I can't obtain root, and RM requires root. Soooo...I'm trying to install CWM via recovery manually or via OCLF. I want to flash a pre-rooted rom...and yes, I have tried all the rooting methods.
Install from package... Finding update package... Opening update package... Verifying update package... E: failed to verify whole-file signature E: signature verification failed