OR You could simply order the standard one ounce Hayes from tower here:

http://www3.towerhobbies.com/cgi-bin...&I=LXZCL2&P=ML

and use it as is there is no need for changing the clunk line in addition you do not have that enormous bung plug. This uses the genuine hayes 'O' ring plug, far far better and of course the O ring is also a form of neoprene.

Here it is using the little diesel MP Jet in my 'Orange Thing'

John