I'll throw my 2 cents. Mine were in way worse condition then yours. Although the intake had 474kmiles at that time . What I did was not the correct way but I basically got some super fine sand paper and gently went across the entire edge to smooth it out. Problem with that is, you can create waves if your not carful. Then I used a 3m disk wheel that's basically like scotch guard material and buffed it as clean as possible. I got it to look better then it was but not nearly as perfect as I wanted..... especially since I was installing it on a new motor..... installed the gaskets and through some permatex on it and torqued it to spec..... I'm still gonna head to the junk yard and try to find a intake with lower miles and better condition for piece of mine... my intake was worse at the ports closest to the fire wall fyi
