The conversion would be called 'Belfast 1979' (because I have no imagination!)...
Basically it is a 'what if?' senario where civil war breaks out in Northern Ireland. The two main sides are an IRA led revolt against a British Army led government force.
I'll skip the background and just go on to the main mod skin lists:
1) UNIFORMS:
IRA/INLA
Basically, ballaclava helmet, camo jacket and jeans ~ you could take 'Stone' from the original GR specialist line-up and give him blue jeans.
INLA could be given black berets.
Governemnet forces:
Infantry: Maybe a 'hackle' for the Black Watch would be too dificult to model (?), so the standard grey beret of the guards regiments with DPM camo would do.
Elite: Parachute Regiment, Red beret with DPM camo.
RUC: All black police uniform.
2) WEAPONS: (The good bit):
Government forces:
ARMY:-
7.62mm L1A1 SLR (British FN FAL with solid butt, all black nylon furniture or some older with wooden stock, etc)
7.62mm L4 'Bren Gun' LMG (As far as I know, no one has modelled the Bren yet - strange as it was the best LMG ever made - better than the US BAR, more accurate and more reliable).
7.62mm GPMG (Based on the FN MAG machine gun)
7.62mm L42 Enfield sniper rifles
RUC:-
9mm H&K MP5
5.56mm Ruger Mini-14
ELITE:
5.56mm Colt AR15 (It's a little known fact that the British Army actually purchased the AR15 - later the M16 - before the US Army did!)
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'TERRORISTS' (depending on your views):
.45 Thompson 1928 (the IRA - allegedly had large stocks of the 1928s which they 'procured' in the 1930s, these were eventually replaced by the AK47/Type 56)
7.62x39mm Type 56 (basically a Chinese AK47)
7.62x39mm SA Vz.58 (a Czech design based on the AK47, but allegedly better)
5.56mm Armalite AR18
7.62mm Armalite AR10
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There you go...
Some nice weapons there - the L1A1 will be a big hit with 'Brits' (best rifle ever made!) and altough there is already an FN FAL Para already in some mods, the solid stocked L1A1 was a semi-auto only (no full auto!).
The AR18 on the other hand (and the Bren) have never been done - the AR18 was an excellent rifle, which was related to the AR15 and looked a bit like an M16 with the carrying handle chopped off, which allowed it to have lots of exotic sighting equipment fitted.
Neither has the Czech Vz.58 been done - although you might say if you've seen an AK47 you've seen a Vz.58! (...Not true...)

The maps would all be urban of course (apart from the opening one which would be called 'Bandit Country' - a term given by the British Army to the border between Northern Ireland and the Republic of Ireland. This farmland was dotted by British Army outposts and observation towers - good sniper country!).
What do you think?