There are great Doopy E-11 build threads here and I'm not going to rehash all the steps of my build. It would be redundant to do so. I did want to contribute some of the techniques I used for my E-11.
Full disclosure, while I do strive to be accurate, I also like to insert some of myself into every prop I build or create. When these things clash, I tend to favor my preference. So veterans, please point out anything I might do here that violates accuracy. I'm not offended by such things and it would be good for anyone reading through this to have those facts.
Here we go.
As many have previously encouraged, replace the resin fasteners with the real hardware. For the grip lock, I used a tapered brass screw and cap nut. Sanding off the edges of the nut provides a nice rounded dome after hollowing out the resin bit on the grip. Although somewhat larger than the real thing, I think the nut here is easier than molding epoxy replacements.
The fire selector knob uses a pin like many other builders have done before. This is not yet epoxied in and will be painted separately.