wetsanding question
 

The 6 Day Detail thread really got me thinking I should wetsand my car. I have a couple of questions though. I know I should wash it first (most likely Dawn to remove any existing waxes, polishes, etc). Then should I clay bar it and rewash before wetsanding, or should I go straight into it?

I would try just clay bar alone.... as for wet sanding... if you aren't careful you will go right through the clear coat.... maybe even the color as well.

I would think 2000 grit would be pretty safe, no?

Ive wetsanded with 2000 grit without any issues. Just dont sit and burn through it for a long time. If this is your first time trying it, find an inconspicuous area and sand it a bit then polish it out. This will give you some confidence that the sanding will polish out easily with a porter cable.
The clay bar will take any existing contaminant off the top of the paint whereas sanding will mill down the paint itself, removing swirls and lights scratches. So essentially, the paper will be doing the same thing as the clay bar while going further, but it couldnt hurt to clay bar first so the paint is a bit more even.