Block Stub Wall - recommendations for how to re-cap

[Black300zx]

My attached garage walls have 3 layers of concrete block which form a foundation onto which the rest of the walls are built. The perimeter has what looks to be aluminum flashing as a barrier between the top of the block wall and the bottom of the framed-out walls, I presume to keep moisture away from non PT lumber. I'm looking for some recommendations to clean up the capping on the block walls, with the following goals:

1. Prevent or slow-down any further corrosion of the flashing.
2. Seal up the cavities to keep critters from making a home in the block cavities. I suspect some are using these gaps to get down into our basement. Complete prevention is unavoidable, but if I can easily minimize them it would be nice
3. Eventually I'd like to trim out and re-paint, so cleaning up these transitions prior would be nice.

Looking forward to your thoughts.

Front corner of the garage. Garage door is just outside the left edge of the photo. The wall to the right of the photo is shared with the main house body.

One of several areas where the flashing has corroded through:

One area where the flashing either doesn't exist, or terminates before the drywall:

 

[i4ni]

Not sure what the flashing is for. Termite barrier? You're not going to stop the corrosion but you could lay another flashing over the top and seal it with butyl or caulk, lay down a sill seal then trim out with wood .Another option If you could borrow a siding brake You could could bend a number of different profiles to easily cover and dress that sill up. Any decent siding guy could seal that up and make it look good in a few hours fairly cheap. Hope that helps

 

[NUTTSGT]

I'd just rip a 2x4 down and screw it to the current sill plate. Close any gaps up with some caulk and paint it.

 

[spudley]

I'd just rip a 2x4 down and screw it to the current sill plate. Close any gaps up with some caulk and paint it.

I have a siding brake and this is what I'd do. Aluminum dents real easy.

 

[ArkTinkerer]

I am currently finishing my shop building. I filled 100% of the cavities in the blocks but wanted a good cap. I found drip edge at the hardware store will wedge over the foam sill insulation I used. I may add some construction adhesive to make sure it is secure. I plan on about 2' of corrugated metal wainscot around the wall on top of that with a j-bend metal to cap it. Finish on all this is galvanized.