Based on previous threads, you should get a lot of disagreement on your question.  

Here is a link that tested the effectiveness of various air filter types, done with state of the art equipment.  It is significant in its comparison of KN type filters, to paper elements:

http://duramax-diesel.com/spicer/index.htm

I use a cheap stainless steel mesh cone with a cotton element, oiled with KN filter oil.  It is a very good filter, for rocks, pebbles and twigs.  I use it anyway because I like the intake noise it provides.

K&N replacement for stock filter.

the k and n apparently will not fit in my 1993. so i i will have to do away with the air box and put a cone filter on the black rubber that goes to the carb

I've been using the cone off this website's store for a little over a year now, and love it.  But i seem to remember a thread about how our carbs breathe, and that the sleeve that connects the carb to the stock air box might direct the air flow better than a cone can.  Think I might check that out after I get her put back together.

I'm looking at my options for a cone filter; already have the HD exhaust. I wasn't sure about the size needed to attach directly to the carb.