Just wondering on this. Our zone is open for trapping fisher (2nd year I think). Am going to set some cubbys but I'm strickly using 1 1/2's. Buddy plans on using a couple 160's possibly. Only thing is our rules state that the 160 (any conibear type) on land can't exceed 6 1/2"X6 1/2", cubby opening not to exceed 50 square inches, conibear recessed (trigger) at least 7" from opening and be set in a watercourse, etc. Made him a cubby and it measures 7"X7" or 49" square (close to 20" long). Cutting slots in 8" so an inch over the 7" rule.
My question is when trying to put the 160 (Duke) in with the top/bottom edges of the trap it seems like it won't work. Wondering if a 120 is a possibility or something anyone specifically uses for fisher?

So your saying the trigger Is going to be up against the top of the box so It wont fire? If that's what your thinking just cut a slot in the top of the box so the trap will fire.

Put your trap in the box with the triggers against the bottom and clamp your springs down on the slots to lift the trigger off the box bottom. If this does not afford your trigger to fire then your box is to small for the trap or your spring slots are to narrow.

Yes I have used 120's successfully for many years for fisher with pan triggers in an elevated leaning pole set. I recess the pan trigger trap 8 inches into the box so the trap is about 4-5" in front of bait at the back of the box. In this situation the animal is stable at the bait, not moving thru or jumping over the pan going to the bait. A fisher will bump it with their chin/chest, while working the bait. This results in a quick humane dispatch virtually every time.

TY. Did some work on his box tonight and had to cut the slots bigger. Bending the springs down did make a difference. Never thought of slotting the bottom or top if needed. Wish we could use this set up on a leaning pole but can't be above watercourse (or highest water level, I know that this can mean flood levels too).
I'm planning on using the leaning poles/trees with cubbies and 1 1/2 coilsprings.
Thanks for the help and pictures. I'm more of a visual person.

I made mine sorta like this dude did. Mine are made for 160 Belisles.

Thank ya MadTrapper375!!! I do fisher with #2 coil because we're only allowed 1 per season but i will now make a coni box or 2