Did you read the post I linked to previously?
MJ/MC does not have a 'sync check box' beside every track, so, if you want to use it to manage your iPod, you will need to look for an alternative route.
The steps outlined in my linked post will get you as close as you can get to a 'tick in a box' scenario.
Yes, there is some initial ground work to do in setting it up, but once that's done, using it is simplicity itself.
Yes, it requires that you add one extra playlist to your syncing options for your iPod, and that playlist will appear on your ipod playlist list, but you can ignore it there. Maybe name it beginning with 'Z' so that it's always last in the list?
The point is, that playlist is always synced, and the contents of that playlist are available for selection using normal ipod methods via artist, album, name etc. etc.
When you tire of a track, select that track while in your new ipod manager view scheme and click in the tick box for that playlist to remove it.
As long as your ipod options are to remove files not in the sync list from the ipod, that track will be removed from the ipod next time you sync.
The view scheme also gives you a one-stop shop where you can list everything currently on your ipod and also manipulate what will or will not be there next time you sync.
If you can't envisage the system from reading, follow the steps any way and see how it works. I think you could be happy enough with the results.
-marko.