How to deal with sap issue - exterior douglas fir

Hello - I've just had installed a new Douglas Fir tongue and groove porch floor. The flooring has already gotten two coats of Woodlife Classic and I will be priming and painting it. Upon closer inspection I found seeping sap. I've read other posts on this topic here and elsewhere. What I have done is dug out the sap as best as I can - there are 13 spots - they are differing sizes - from 2" - 5" long and about 1/4" - 3/8" deep. 3 out of the 13 have a diagonal vein of sap that runs deep and I'm afraid to go any deeper - the boards are 5/8" thick and I don't want to go all the way through. What I have read is to prime with BIN and then fill with a wood epoxy, however I have found two different opinions on which should go first. So, my questions are: 1) which goes first, the epoxy or BIN? 2) Can I leave the deeper veins as they are and just clean them out as best as I can? 3) When I dug out the sappy parts, the wood is pretty rough - will the epoxy better adhere to a rough surface or should I sand the gouges smooth? 4) I know sanding will be required once all is said and done - should I retouch the Woodlife? Thank you for your help!