You just buy a glow fuel tank like you would normally from Tower. Then you buy a replacement plug. Brown for gas, black for glow. Make sure you use tygon or some other gas safe fuel tubing.
stopper
http://www3.towerhobbies.com/cgi-bin...?&I=LXD755&P=0
fuel line
http://www3.towerhobbies.com/cgi-bin...?&I=LXD737&P=0
Tygon is a bit finiky to use. It tends to harden up and swell causing leaks. You need to use zip ties to hold it in place. I use wire ties, just dont twist too tight. When the tygon swells it can cut into it. You can also use brass fuel tube barbs, but you have to solder that onto the brass tube. I use a blue fuel line from B&B Specialties, Easy Flex Gas Line B&B web site is a little hard to navigate. If you just download their catalog and go to page 6, it has the fuel line. B&B is a really low overhead company.
brass barb
http://www3.towerhobbies.com/cgi-bin...?&I=LXWH38&P=0
Edwin