Go to Lowe's get 3/8 OD 30'' PEX Faucet connector part no 3830LPEX tube .use 7/32 Allen wrench holding the tube start making slow circles expanding the opening about 5/8 ''deep check it with a fired case.when you can get the neck in firm it will hold the brass. Next cut it about 12''and trim the top to fit the funnel. Referring back to December 13 Daily Bulletin it explains how. Good Shooting Larry