Small oil leak

I had this EXACT same problem when I put an airgap intake on my 360. It think it was not sealed enough in corners of the back of the intake where it really needs more of the goop stuff. I also used the cheapo sealer from jegs. I took it off and re-did it with "Right Stuff" brand sealer. It works awesome for sealing intakes.
What intake and valve covers are you using?