Cover the aluminum strip carefully and sand away, be very careful as the veneer is thin and you don’t want to rub through it, I have used beeswax as the final polish and finish in the past. 

For the dents, you could try to steam it a bit and see, if the dented veneer will rise a little.
Place a soft wet cloth over the dents and then an iron.
Careful of course as you don't want to burn the veneer.

Martin

Collect the rosewood sanding dust as you do the sanding (and sand by hand of course). It can be mixed with some wood glue/filler to patch large dents and gaps. That will retain a little of the color to help hide the scar.

-sonavor

Thanks all, here's a quick update. 

I was able to sand down the scratch as it wasn't very deep. I used some epoxy with sanding dust to fill a small dent and sanded the surface using 220/280/400 grit. After applying multiple layers of boiled linseed oil I'm pretty happy with the result. It's not perfect, the satin gloss is somewhat uneven in certain areas (yes, I did rub off excess oil) but only noticeable in certain light angles from up close. 

Here's the B400 fully assembled...

Very nice.  That is a great result. Well done.

-sonavor