R1 Subframe For FZR 1000 Tail swap any info/advice?

Hey guys I'm considering a Tail swap on my 1987 Yamaha FZR 1000.

I bought the Tail plastics and rider seat (Apparently from a 2007/2008 bike) ridiculously cheap on ebay and I was wondering the best way to go about a tail swap.

I've read heaps of forums on this but I'm undecided whether i should either:

1:Cut and modify the existing sub frame

2:Buy a R1 sub frame and mount that.

If so, I know they changed the sub frames in 09 but are all the previous years the same size etc??

Or 3: make a new sub frame....and by that I mean, I have a mate who is a boiler maker and he has agreed to try and make one if I pay for materials.

If so what materials would be best and does anyone have any plans of the design or a better one??

I also only have access to a stick welder...Would that be sufficient?

If not I'd try and hire/borrow a TIG.

Thanks everyone!