need little info on k3 vs k4 onwards parts

You need it welding by a fabricator really who knows how to use the correct gear for the job . There are some alloys that need heat treating and annealing after welding , there are some that don`t and a good fabricator will know the pitfalls . The main part you weld onto is usually cast anyway and the subrame will be made from extruded metal , all that carries it`s own set of problems in it`s own right .

Thats leads onto the safety aspect, dont want to cobble a subframe together for it to fall apart riding down the road.

Although did have another idea today. A curvy subframe wont take the plastics, but with the cutting off the unecessary bits the panels are close enough, and the clufixes (those m6 threaded cylinders which are fitted into the frame for bolts to screw into) can be done at work, along with extra drilling or bracket mods, so thinking of trying that direction now and my subframe has already been cut to fit the pointy light so wont be of any use to put my snow plough back on.

Havent given up just yet

That sounds like an easy route , a bit of Meccano to see how it goes aesthetically

Pointy subframes are made from painted mild steel, either that or those clever slanty-eyed little monkey brain munchers have developed a new aluminium alloy that rusts like steel does.

Just mate front of curvy subframe to rear of pointy one - any half decent welder should be able to do that once you've worked out exactly where to cut both to get the panels to line up with the seat and tank.

There shouldn't be any need to have any alloy welding done to the frame to get the right effect.

Doh , yeah they are steel , the Frame itself is Ally though , subframe is made of Mild Rustoleum

ive got a late pointy subframe thats made of ally lozzo

anyway when/if I do actually get it done will post up pics of it for flaming/mick taking value