valve lapping...and heads

the chemical that i used to clean the valves after the lapping leaves a whitish residue, and for the most part the valve guides were in decent shape with little wear (i had 48 valves to choose from), as far as the heads i rinsed them a few times and blew them out prior to install, as far as the heads valve guides wearing the heads i have on now will probably be throwaways in a year when i replace them with aluminum heads or refurbished 906's with hardened seats and new valves, im hoping they can take a bit of a beating in the next while,