Had a rover 216 and a K&N. i had it attached directly to the throttle body. however i didnt think this was appropriate in the elise.....
purchase 135 degree angled black drainpipe joint from homebase, elimate wide lip from one end with saw. roughen the surfaces which will be gripped by the jubilee clips via the rubber of the filter and hose to increase grip.
Remove air box lid only, keeping flexible hose to throttle body attached
Assemble!
You will find that it will lie beautifully on top of the bottom half of airbox and sheltered from rain and debris, but with excellent cold air supply...enjoy!!
Total cost £48 i think
I will try to post a photo...dont know easiest way though. Will need to get car back from bodyshop first tho - getting new front end as taxi driver caused superficial damage by prising my door open beyond its limit out of my hand...long story, more info to come re. that!
Cheap DIY K&N Induction
kinda like this:

ninjaSanjoy wrote:http://prasad.it/misc/naf/index.htm
Don't listen to them they only want to spend your money ....
