I went by a local polishing shop with the XF to see how much some polishing work would cost. They have a S/C, a turbo, and other items in their display case and they do quality work. They did the SS exhaust on my 650.

Here is the quote they gave me:

Plenum Covers (both) - - $70 - smoothed and polished
Valve Covers (both) - - $130 - - casting cleaned and polished
SuperCharger - - $95 - - polished (must remove from car)

They offered me 10% discount if I brought in more then just one item
ie.. both the plenum and the valve covers, SC and valve covers..etc..

What you think - $180 for the Plenum and Valve covers? I can wait on the S/C as I don't want to R&R it just yet. I need to install the LET plenum spacers anyway - so yank the valve covers?