I have been bothered most of my life by pinching the arrow nock.  I was envious at times of the spacer that was available on shooting tabs but never seen one on a shooting glove.

I made this finger ring out of scrap leather:

 

 

 

The pad is concaved just a little to index the index finger along the middle finger.

I dont know if I am the first to ever try anything like this but it really helped me out.  No more callous on the edge of my finger and nail too.

Neat trick! Can't remember seeing it used before....I do know a couple guys who use spacer blocks with gloves...but that's more to get the arrow closer to the eye, without changing anchor.

That will also give you a reference for consitent placement of the first finger on the string.