another fuel sending unit question

i'm going to put the 15 gallon fuel tank in the back,i got my sending unit and gauge and wanted to check it on the bench. the sending unit and the gauge work together,now the question. i was wondering if there is a correct adjustment of the tangs that limit the traval of the float arm? bob

 

A simple solution would be to measure from tank top to bottom then measure from the underside of the sender to the bottom of the float and compare. I suspect the limiting stops are there to protect the float from damage. Banging on the top or bottom of the tank would not do the float any good.