If any pieces of the guides are in the oil pan, make sure you get them out! The PO of my truck replaced the timing chain, but just left the broken guide pieces in the oil man.
It sucked the pieces onto the oil pickup, which killed my oil pressure, and it eventually led to the new timing chain skipping and killing the engine. I had to take out the engine and put a different one in because I didn't have time to deal with it at the time. Now I am rebuilding it, and the engine looks brand new with 150,000 mi on it (I have not looked at the valves yet, but there are no marks on the pistons). SO, don't leave chunks in the oil pan!!
