I will llook at one later today but I thought that the pins had a retention groove and they kind of "snapped" in on an internal spring that caught the groove. I am not sure on this but I know some have this and I thought the Winchesters did too. Have you ever dissasembled the trigger group? possible got a spring out of the little slot in the retention pin hole?
Just something to check.
CPL holder since 1991, NRA Lifetime Member, DU Member, NICET certified
"For those who would give up essential liberty to purchase a little temporary safety, deserve neither Liberty nor safety.—Ben Franklin.”