When the 1.0mm Globals come out I'll probably buy a couple, but I think the 1.6mm will still be the ultimate stamped receiver. I've built 3 so far and they are my favorite "store bought".
I use a 3 inch grinding disk in my chinese mini-mill to rough thin the trunions, then finish with a light clean up pass with an end mill. If you don't have the tools, I think it could be done with grinder, dremel, files - and lots of care and patience. Trunions are hard. You could always send in your trunion for Global to thin for you for $12. The rear trunion is a piece of cake to do with a belt sander - no need to worry about it.
You will have to thin the upper rails where they fit into the trunion grooves - or widen the grooves. I widen the grooves with a slitting saw on a mill. The Global instructions are good, you can do this with a file.
If you dimple your countersunk rivet holes (you should), make sure to support the receiver on the inside when you do it. It takes alot of oomph to countersink dimple 1.6mm.
The "dimple" controversy is kind of strange to me. People seem to think that because the magwell dimple doesn't match a FEG (Hungarian), it isn't in spec. There are a bunch of different dimple shapes - FEG is only one of them and it isn't really "average". Because there are a bunch of authentic dimple shapes, in order to be "accurate" to an anal degree, you would have to have a bunch of receiver models based on dimples. I sort of doubt that Jimmy is going to tool up to make an exact reproduction of every obscure dimple variant.
s & p