It will help, specialy if you put low restriction slip on muff's & if it has not already been done jet the carb.

but i would expect a bike that old to have low restriction muffs?

if carb is as it came from factory new you can put a small electrical brass washer under the needle, this is a cheap easy way to richen fuel curve as it rases the needle so the tapper comes in earlier. just be very very careful removing the top of the CV & replacing the top, not to damage the rubber diampram.

good luck

ps, about fuel economy, an over lean carb can use more fuel, with the SE aircleaner  it is possible it might help economy, but in most cases the owner feels the way its going and want to use the extra horses. so just have to wait see, some say use more fuel some don't.

just remembered, Bobby Woods, from Woods performance carbs ( google it) has a needle you could fit i think its a K1 and it would help get better economy, they also make bike idle and feel nice. reason they help economy is they use a stepped Needle not a Tappered Needle. i have used a Woods Reble 43.5 carb and worked great and got really good economy on runs, but mostly due to the stepped needle.