Shock travel

I am building a new xs. I have new seat rails and 11.5" progressive shocks. I am not sure if I am going to attach the fender to the swing-arm or the new seat rails.

Suggestions?

Also if by the seat rails what is the average travel distance allowance from tire to fender. Just an average I understands riders weight and shock settings and spring stiffness.

Pics would be great. Thanks for any replies.

On a stock bike the rear wheel travel is 3.152 inches., that's with a shock of 12 3/4 inches.
An 11.5 inch shock will give less travel. Not 2 + inches less but less. Maybe around 2.875 or so.
So if your fender is frame mounted you want the clearance to be more than the rear wheel travel. If rerar wheeltravel is 2.875 inches, then having 3 inches of clearance between the fender and tire should be ok.
Leo

Exactly the info I needed. thanks.