Hopefully you'll have all the suspension pieces off for a rebuild, just treat them to a bit of time in the blast cabinet, wash, dry, and scuff them and shoot some epoxy primer on them....

For the little bit on the cowl, I'd use a small hand held sandblaster. They don't have near the pressure of the big blasters and won't damage the cowl. Got a hand held blaster off the Matco truck awhile back for $45.00, does a great job on small areas.