No matter if you're going to 75mm or to NTN, unbolt your BMFs from your switch plate and install the new toe cages per the included instructions. It takes some tools and a little mechanical skill. Check out the instructions for a BMF/R conversion here. If you are not comfortable, choose Conversion Service, ship them to us and we will ship them back to you ready to rock.
NTN to 75mm conversion kit: You will receive Toe Cages parts, and your BMFs will now be compatible with the older telemark standard, 75mm Telemark Boots. Also known as "duck bill" telemark boots, these comfy, powerful boots have longer soles coming off the front of the boots.
75mm to NTN conversion kit: You will receive Toe Cages parts, and your BMFs will now be compatible with NTN Telemark Boots or "New Telemark Norm". These are a newer style of boot that has a short toe sole similar to Alpine or AT ski boots.
In both cases, your bindings will be attached to the back heel of the boot for a sweet, natural flex. The Real Heel Feel.
Note: the BMF/3 conversion is more expensive as it is the entire front end of the binding.