rigging piston for a V engine

have not done any rigging in a long time so need some help !

I got this simple piston rig but piston is vertical
and need to modify that for a V engine at 60 degrees

hope it can be done

when I rotate the 2 top bones I have to do it in edit mode and get the 60 degrees angle
should I reset the angle of each rotated bone ?

thanks for any help