I tried the round K&N filters on my 62 tri-carb several years ago but as I recall the space was too tight to fit the front filter, and I ended up giving them to a Volvo friend of mine who used them on his 544. Maybe I could have adapted them, but apart from washing and waxing, and posing for the camera, my technical skills are limited. I have those cheap pancake style filters on now but am going back to stock.
Elrey - what do you run on your tri-carb?
Just incidentally,and speaking of K&N, I switched to their oil filters (#2009) a while back (I mounted a spin-on housing back in the Jurassic period) and found them to be excellent, altho a bit more expensive than Wix or Fram, etc.
Thanks to those who replied, and in my case for all of you who patiently take the time to respond to both the usually really dumb and occasional technical questions - otherwise I'd be driving a Mazda Miata.
Cheers
Dave