I asked for help (thanks for suggestions) in the removal of the factory nocks from my TAC15
arrows and here is how I solved my problem. I found a video on YouTube where the guy buys a 1/8" x 4' steel rod from Lowe's and cuts it in half. He then removes the broad head from the arrow and shoves the rod inside the arrow until it makes contact with the nock. He then holds the arrow with the steel rod inserted in one hand and gently taps the exposed end of the rod with a hammer and slowly drives the nock out of the arrow. I tried it and it works without damaging the arrow shaft or the factory nock. The nocks were not glued in place which made them easier to remove and they look to be reusable.
I also found that the FireNock nock is a little warped or oval shaped (not perfectly round) when it is assembled to the light circuit board making it difficult to install in the arrow shaft. I very carefully compressed the open end of the arrow just slightly with a pair of pliers making it oval shaped also which made it very easy to insert the assembled FireNock. The FireNock seems to fit very tightly without having to install the Bulldog collar. Tomorrow is the big test to see if I have a successful assembly or not.
I tested the FireNock operation by dropping it nock first about 6" onto my work bench top and the light turned on solid for about 6 seconds and then started flashing. I dropped it a second time about 6" on the work bench top and turned it off. I could not find a test anywhere on the FireNock instructions for turning the light on. I discovered it accidentally while assembling the arrows. Hope this info helps others.