Dwight,
Thanks for sharing your knowledge. I finished my bag today with 12 gauge (12 mil) plastic from JoAnns. I have the same pump from Harbor Freight that you linked above, though I bought it before I saw the link. I made the bag fitting with parts from Lowe's. After this photo was taken, I drilled a hole through the bushing on the inside to keep the bag from blocking the vacuum. Thanks again for sharing.
Randy