Its not to difficult to make vacuum pucks for small work, but for your job I would use the masking tape and superglue method,
Apply a layer of masking tape to your plywood. Make sure tape is behind the small parts.
Apply a layer of masking tape to your wasteboard over where you would mount the job.
Apply wavy lines of superglue to the tape on the back o your plywood (or whatever)
Press the plywood to the masked area on your spoilboard.
You will not need tabs.to cut your pieces. When you are done just peel the tape from the spoilboard and the backs of your small pieces.
If you google around there are some youtubes illustrating this method. Set the DOC to the plywood thickness and the thickness of the tape will keep the tool off the spoilboard.
This method work well on woods and plastics. Would work on metal except for lube soaking the tape.