Cartridge lead help....

Having bored folk to death with regard to a Sumiko Blue Point vs. a Shure M97xE and various phono stages,I am now certain that the "problem" is due to one or more of the cartridge leads....not only are the contact sleeves? in very poor condition,I also suspect there may a break/loose solder joint somewhere....when everything is in synch,it sounds wonderful....then an hour or so later flat,dull and lifeless.
So buy a new set of leads you cry. I wish.My Jelco head shell connects to the arm tube via some sort of din plug arrangement...I only have "pins" at the cartridge end of the leads.Would it be possible/easy just to cut the leads back as far as possible and then solder new attachments? Never done it before so a little wary,or is there any other course of action I could explore?