Has anyone tried and/or ever considered building a faux-M320-ish launcher by [heavily] modifying a Spike's Side-Opening Havoc?  

To the natural question of "why," the best answer I can give is, frankly, "why not."    Given that the better half has been blocking my attempts to purchase an M203 I've been considering if I couldn't build a faux-M320 piece by piece and disperse some of the one-time costs...

Obviously it wouldn't be a "faithful" replica, just emulate some of the form-factor and major functions of the M320 - but just in looking at some photographs of the Havoc and its accessories, and comparing them to the M320, this is what I'm thinking:

9" Havoc Side-Opening launcher - have the barrel turned down to a more "smooth" tube, eradicating the "grip surface" pattern
The pistol-grip/stock adapter component of the Kaos chassis
The B5 pistol grip (cut down)
Custom-built (probably polymer and/or aluminum) "frame" that would incorporate mounting points for a side-mounted sighting system, and a bottom rail, upon which an LWRCi (or similar) folding VFG could be installed

The only thing that I don't have a good solution for [at least in my head] is how to do the sliding stock in a way that allows it to be adjusted quickly to at least two positions, but be easily removable for rail-mounting the launcher.

Some comparison photographs -

"Off the shelf" components:
















M320:










I know the question of whether or not anyone has ever tried or anything similar it is a bit of a long shot - but can anyone see/think of reason it wouldn't work/shouldn't be done, or perhaps owns a side-opening Havoc, and can comment on the potential feasibility of it?  

Is it just simply not worth it for something that will only superficially resemble the M320?

This is obviously a project in the very, very exploratory phases...  

~Augee