I HAVE A QUESTION!!!

i got pulled over in PA doing 93 in a 55....the cop gave me a ticket for 75 in a 55 but wrote down 93 and circled it at the bottom and said that if i tried to fight the ticket that he would come in and the judge would know i was really going 93, not 75 and id get fucked in the ass. my dad wants to take it in to "plea bargain" court and try to get the POINTS reduced, not the fine and thinks that the cop cant charge me with a 93 in a 55, because the ticket is for a 75 and he cant change that. is it worth it? can the cop/judge change it like that?