Thinking of a 98 F150, info please!!

I am very close to purchasing a 1998 F150 2wd V8 Extended Cab with 104k on it, before I do so I wanted to know if there were any major mechanical flaws that I should be aware of. The first thing that I would want to do is add an intake. I would like to know, if I were to get an ebay unit (example http://cgi.ebay.com/ebaymotors/97-02-Ford-F150-4-6L-5-4L-V8-Air-Intake-System-01-99-98_W0QQcmdZViewItemQQcategoryZ38634QQihZ011QQitemZ 320019419102QQrdZ1) is there any modding that I have to do, or does it bolt right up? Do these units take into consideration the mass air flow sensor? Does anyone have a picture of one of these type units installed? Am I better off getting an expensive K&N unit? Also, what size speakers would I have to get if I were to replace the stock ones?

Thanks,
Ken