Ivan is an old friend of mine; I live near him in Rockland County, NY. He's somehwat of an odd dude at times, but very fussy about getting things done right, and a good guy overall. I have his needles in my current '98 B12, and highly recommend.
I'm running a Yosh RS-3 end can, stock paper filter (never had luck with K&N's over years/bikes).. stock pilots.. and I think I'm one size up on the mains (I forget and I'm out on business in China now). The key thing was getting the needles and fuel-screws to jibe. As I remember (ah, sh*t), I think I was pretty wide with the fuel screws and somewhere in the middle of the needles. [How's THAT for helpful?? When I get back I'll post my exact settings.. which I've used for both my 1st Gen B12's to good effect].
Don't forget to drill 15 1/2" holes in the top/back of your airbox, and chuck out the snorkel.
PS... my B12's have been NOTORIOUS for running crappy when the air filter gets even slightly dirty (you often can't tell by looking). This just might be due to my tuning..
Anyway, the Black Bastid runs great, no flat spots right to redline.
Suggestions welcomed!