Disclosed are wellbore flow control devices that allow on-site field adjustments to flow characteristics. One disclosed well system includes a base pipe defining one or more flow ports and an interior, a first end ring and a second end ring each arranged about the base pipe, the second end ring being axially-offset from the first end ring such that a fluid compartment is defined therebetween, an autonomous inflow control device (AICD) arranged within the fluid compartment and having at least one fluid inlet and an outlet in fluid communication with the one or more flow ports, and a sleeve removably coupled to the first and second end rings and configured to be removed to provide access to the fluid compartment and the AICD in order to make on-site fluid flow adjustments to the AICD.