Fuel level float arm length??? a 33 gallon tank.

[Dlwusmc]

That is all i am Missing off of my 1991 bronco 5.0l. When I replaced the fuel pump I discovered the arm And the float are both Missing. I've tried aftermarkedt and none of them worked correctly.I found a place that sells a 23 inch arm with a float on it that can be cut to size, I just need to know how long it is Supposed to be.