How to clean Stubborn Records

I've been having trouble with a few LPs that just don't want to come clean. I've been able to reduce the crackle and pop, but there is still a decent amount of it, along with constant surface noise. This may just indicate that the albums are worn out, but I hear no distortion in loud passages, nor is there a lack of dynamic range. To clean the albums, I first apply a solution of 1 part rubbing alcohol, 2 parts distilled water, with a few drops of detergent. I then use a paint brush to do a little scrubbing (the bristles have been cut down to about 1.5 inches long to enable scrubbing). After that, I put the LP on a dish rack vertically and rinse off with steam. I repeat for the other side, then put it through my Spin-Clean unit to remove any left over residue. The record is then lightly wiped, then air dried.

Are there any suggestions here to help me remove even more of the crack and pop? The method I described does clear up sound clarity in the higher frequencies, but it seems like there is still dirt on the record, as if the cleaning process loosened the dirt, but didn't fully remove it. Would a vacuum dramatically improve this?