20v extractors on my Ae92 Help!!

[Ae92 Levin]

Ok I got given some old custom made 4-1 extractors with a few small holes and things, and was going to put them on my Bigport 4age Ae92 Levin (after fixing them up of course) when I got the opportunity to buy some factory blacktop 4-2-1 extractors which I have been told are better than 4-1 when fitted to a 16v 4age. I have also read that it is fairly straightforward with the only prob bein that the end holes need to be re-drilled or slotted.. SO I took off all my covers and crap and measured the clearance between the head and the radiator, then measured the 4-2-1s and found that (although my measurements probably werent exact) there would be very little, if any clearance between the extractors and the radiator..
So basically what I'm asking is has anyone out there done this swap and knows if they will or wont fit, or what needs to be done to make them fit, and also if it is true that the 4-2-1s will make much more diff over my fairly rugged 4-1s?

Sorry its a bit long-winded but any help would be much appreciated as I'm supposed to be fitting them on monday.
Cheers

[Bazda]

shuld have the same/similar clearances between both eng bays.

[Ae92 Levin]

Hmm.. ok cheers. the ae92 is lookin damn sexy btw baz