i keep around one of those universal "chrome" like flexy hose type things that go from the air cleaner snorkel to the tin heat stove on the exhaust manifold.
the universal types are pretty long, and when i need a particular hose shape, i will form that thing into position, then go to the parts store and look at the hoses on the wall to see if there is something close to the shape i have formed.
those things work pretty good for this.
when done, i straighten it out, push it back together, and put it back into the package for the next time.