Questions about oil bath air cleaner

[Spitshineschwinn]

The stock air cleaner on my 59 Apache appears different than most I've seen. It does not have the screen slot below the top, and I have a hard time imagining how enough air can enter. I am seriously considering replacing it with a chrome aftermarket cleaner. The truck runs good as it is, but the idle has to be set at between 800-900 RPM so it does not die when stopped. Any comments/suggestions? Thanks in advance

[magicoolbus]

That is the same Air Filter that I have. I highly doubt that the airfilter is causing enough restriction to bog down your engine at the proper idle setting of 550. Unless the mess element is completely crusty and plugged. That's the nice thing about oil bath. If dirty, just rinse the inside mesh and change out the oil with a 50wt. and gittyup.
Now if the inside is missing, the lid may be setting down too far causing an air restriction. If the inside is gone, you are not getting any air cleaning either.
Please don't go with an aftermarke chrome paper element. The air cleaning ability of the inertial air separation is very efficient.