Need help with MG34 on a MG3 Lafette.

[m4a1sof]

I want to mount an MG34 onto an MG3 Lafette tripod. I have the TNW adapter block for the barrel shroud latch, but was wondering how to modify the trigger lever to be able to switch between the lower portion of the MG34 trigger and the upper portion to have semi and full capability like the original Lafette 34 has. Has anyone done this and could you describe and maybe even post a photo of how you did it, or does anyone know of someone who makes an adapter for this. Thanks in advance.