I drilled about 50 #10 galvanized Deckmate screws into my new fence before realizing they are too long, and sticking out the back of the 2x4 the fence pickets are drilled to by 1/4 in.
One of the answers in a similar post suggests using 4 1/2 inch side grinder, "Very carefully." Would this work in my scenario? What does "Very Carefully" mean? Would a 7" grinder be more effective? Does this method contemplate ruining 50 grinder blades? Would it be less expensive and/or faster to remove and replace the screws with with shorter #8 screws, or does this significantly compromise the strength of the fence?
UPDATE TO POST
Thank you all very much for the answers and insight. It never occured to me that #12 2" screws might be found online. Since the local hardware doesn't sell them, I assumed they didn't exist. Today I counteed out exactly how many of the shorter #12 screws to order, and realized the 50 I estimated above is way off; it's more like 250.
My inclination at this point is to cut the ends off with a reciprocating saw as Nate suggests below. Is a specific type of saw blade or technique recommended for cutting nails?
I also failed to recognize the rust problem Nate identified, and wonder if the superhero-ultraviolet-blocking paint sheild that I am double-coating the fence with might prevent the cutoff ends of the screws from rusting?