Peter T......The way you described the covering process is exactly how you do it. Its a bit time consuming but renders a very nice looking SD in the end.
Plus you can take pride at the field (when someone asks about it) that you did it yourself. Just make templets off the plans, I would avoid cutting up your plans and protect them.

Peter make your templets from see thru paper and transfer to poster board and then to the covering OR trimsheet. Once you have your star and burst bar cut out - you can spray down some dish washing soap and water (light soapy solution) and apply the star and bar together or separately. Use a credit card or Drivers Lic to lightly squeegee out the soap and water. This will in effect cause the now star/bar to stick down and become stuck.

After it drys (24 hrs later) you can apply (for covering) some heat carefully and it will activate the adhesive in it. I would lay down some pin strip on the edge and then seal the pin strip with either clear Rustolium paint OR - go raid your wife or GF's finger nail polish bag and steal the clearpolish sealer and paint the edges. Let dry. Done- repeat all other surfaces. I wish you good luck and just take your time and it will very nice!