I assume that you are using Video 0048. The EFC for Set is 200, and most remotes have that on Enter or OK or Select.

You can assign this EFC to any button by making sure that you have pressed the VCR device mode button and then:

1) Press Setup until 2 blinks
2) Enter 994 (2 blinks)
3) Press Setup briefly
4) Enter 200
5) Press the button that you want to provide the Set function.

The remote will blink twice if this is accepted.