Nah then lad, firstly nowt wrong with us big lads (6' 1" and 18 1/2 stone me'sel and I'm originally from Blackburn so I'm not taking the proverbial!) and definitely nothing wrong with smaller bikes!
I've had big bikes and small bikes and for chuckability without going all F1, knee down b*llocks you can't beat 'em. Mike also hit the nail on the head, they are cheap as chips both to buy and to work on.
Don't know about the older tanks, I suspect the answer is yes, simply because the basic shape didn't change much during the production run so they are more likely to have modded the tank, seat and panels than drastically altered the frame.
So, no p*ss taking here, just ask away, post up piccies as you go and good luck with the build.
P.S. you might want to take a look here for ideas and possible inspiration
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