Advice: Going from 126mm to 130mm spacing. Is it safe?

I can't see that working: the stays are pushing against each other, so there is no way of controlling the amount each stay is bent.

I've done it this way before, just count the rotations and set up some string to guide symmetry. Works a treat.
I always found sheldons 2x4 technique a bit hit and miss in getting accuracy. Though some people have had issues before whereby this technique affects the alignment of the drop outs from the stays