To make the holes the same shape and radius,as original make a buck out of a pine 2x4 that fits the inside radius of the air cleaner. Make a cutout in the pine the same shape and radius that the sheetmetal cutout needs to be.
Make your cutouts in the air cleaner housing smaller than they need to be, clamp your pine buck to the inside of the air cleaner behind your cutout. Using the round end of a ball pein hammer, and a small autobody hammer tap the cutout to fit against the rounded cutout in the pine buck.
Once everything is shaped, trim the excess back to a smooth shape, the internal baffles look pretty easy. Grab another air cleaner base, and cut them out of this one, and tack weld em.into place.
This is how i would do it
Hope this helps.
Matt
