Best to use dielectric grease - it won't "insulate" the clamp/post connection. Another trick I learned back in the day to prevent corrosion build-up on the posts - epoxy a penny about 1" away from each post. This "draws" the corrsion towards the copper and is much easier to monitor & clean than build-up on the posts. Good luck.

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TAZ

'84 300D Turbo - 250+K