try a little oil on a q tip to the inside of the line that might help it slide on.
DO NOT leave it the way it is. That line is filled with pressurized gasoline and sits over a running engine. A little oil or grease on the barbed part and inside the line can help it slide on.
FWIW, you can also use spit to lubricate new hoses for installaion. Yeah, it may sound funny but the official Ural assembly instructions actually state this several times. They just put one together at the shop and were telling me.Scott