I recently started using my 716 daily since receiving my custom built rod by Jason. The drag knobs are a weak point on the 716.So I ordered the cheapest drag knob I could find for science & painted it with Krylon Fusion all-in-one paint ( matte white). I put the OEM knob away & will update as time goes on. I am not sure if this knob is Delrin or not? I figured the matte white wouldn't stand out like gloss paint might. I put several light coats on & sanded some with wet/dry sand paper. The OEM knobs seem to yellow with age.
I am no machinist but was curious if the drag knobs could be made from metal like the old DQ knobs were & powder coated? It seems most offerings of the aftermarket knobs are black maybe the demand isn't high enough use white Delrin?
I don`t have a 716 to measure , but it maybe very possible using a quick spool nut . I would think that you would have to run a tap thru the nut for american thread .
Another possibly is a Mitchell nut ,same thing need to retap ?