Here's my favorite wood block. The width is about perfect to tackle
a run.

A trick a tradie told me to do to remove decent sized runs is get some fine filler and just skim a light coat of it over the run. Then get some 600 or 800 wet and rub it with a block until you knock down the run so its level with the filler. Now get some 1500 wet on the block and knock it down more , then finally some 2000. Once the filler is removed the run should be removed.(ive never done this trick before, but ive seen it done and most of the time is supposed to work a treat)

I have not had too much time to work on the car but here is the current status after sanding the runs only with 600 grit and then block sanding wet with 1000 grit.



Close up:

Seeing as you've blocked that area, won't you need to do the rest of the panel or car to get it all flat. First pics shows a little texture in it. Or you're going to colorsand it anyway?

Keep us updated......

Yes, I am going to color sand the entire car.

That's looking really good, nice job!