Here is the procedure I followed to change the fuel hose and vent hose on my 2005 Parker 2510.
BOM
A2 Fuel Hose, 1-1/2” inner diameter for fill line, and 5/8” inner diameter for vent line
Hose clamps (4) for fill hose, SAE size 28 (Amazon.com: Scandvik 08134037045 Stainless Steel Hose Clamp...