http://cgi.ebay.com/ebaymotors/Honda-CBR600F4i-Tail-CBR600-F4i-CBR-600F4i-Rear-Cowl_W0QQcmdZViewItemQQcategoryZ35583QQihZ018QQitemZ280126933793QQrdZ1QQsspagenameZWDVW
How much work would I have to do as far as the cowls go and both seats?

I myself dunno but it would look bad-arsed bro ... good luck , and make sure to show it off if you get it and get it installed 

The "easiest" way would be to cut off the GS subframe.  Then weld the F4i subframe to the GS frame...

The only problem would be the fitment between the seat and the tank.

Ditto think you whould have to get the whole sub frame.  I think Sinrath did it once. . or was thinking about it. . .I'm old and forget things

Hey Srinath can you give me some assistance please.

oh yeah and some pics if yah got any

OK I never have done this, I've just sat the tail section on my frame, worse yet, my tail is the one (Maybe F4 not F4 I ) that has a single seat ... or this clown is lying about this ... cos there is a wrecked F4I with a tail like mine ...
So, no clue, but at least, it doesn't look like this tail.
Cool.
Srinath.