Oh yea, nevermind then. I thought that you were actually looking to go through a CCNA based academy first, then take the exam. Yea, with a 599 on the Network+, personally I wouldn't even think about touching the CCENT yet. I would most certainly study more. My opinion with technology company based certifications... treat them with the same respect as you would with the company that you are willing to present the certification to in your career hunt. If you are placing a CCNA acronym on your resume, I would hope that it wasn't due to memorization. In my opinion, those people...and they exist in HIGH numbers, are just classified as cert hunters. They seem to think that it going to help them with the ratio of other applicants on the table.
Personally, and this may sound cruel... but, anyone that is willing to apply for a job that places them in a DIRECT responsibility with what the CCNA represents...and they simply have no job experience and just memorized a bunch of stuff, I would send back to school... or out of my sight or contact. I really wouldn't want to work with someone that has a CCNA and really doesn't know what they are doing. I've done it before and ended up teaching them about everything more than working... LOL
A CCENT is something a little different though. Do your self study with your Sybex guide and then take practice exams. See how you measure up. If you find that you are still having problems, perhaps try and search for a different guide. I can relate to your learning disability, a lot have it. You certainly WOULD NOT be alone in the work force with other CCNAs ... heck, even CCNPs that have similar symptoms.
Sometimes you also just need something taught to you in a SLIGHTLY different way in order for that light bulb to go off. For instance: When I was in the cisco academy, we were in a fast track while on subnetting. There were about 3 people out of 24 or so that just didn't get it. All it took was for someone else to get up in front of the class to explain it in a SLIGHTLY different way than the instructor and then, POOF..they got it and we moved on.
I would rather be THAT guy rather than another situation I was involved in where I asked someone to walk over to the router and tell me which lights were on and to switch a cable from one port to another. He walked over to a 3750 and said that he needed to clarify what port to switch out again... I said, well for starters, thats a 3750.... you aren't even at the right device... you may want to check out the 1841 over there...