No. Definitely no. 2d widget material is exceptionally simplistic.
In this case, find the material the 3d widget is using, make a copy, move it to your project, open that copy and add the code you have in your own material on top everything else it is doing.
This way you’ll preserve the pass through material (there’s like 5-6 different versions there - I think they’re actually dynamic instances, too) and can add your own fancy stuff to it.
Untested, never seen anyone trying to do it. Let us know how (if) it works out!