Found plastic chunks in the bottom of my oil pan, so I figured that clanking sound was my timing chain guides missing and not just noisy valves... so I bought 2 new guides but when I took the valve cover off and it looks like I do have guides?? Is it possible that only part of the guide(s) broke off?

 

From above you are only seeing a little bit of the guides so you could still have broken guides. It also looks like the passenger side guide might be broken on the upper side. Also if there had ever been a timing chain job done in the past a lot of times folks do drop the pan and fish out the pieces.

 

Part of your guide has broken off. You need to replace your guides.