3sGTE Stem seals....

Righty. I have a decision to make. 12 months ago, while replacing my turbo,
I found a dribble of oil down one of number 4's exhaust valves. It was only
tiny and I had to get the car running again ASAP so I left it alone. With
the turbo replaced I noticed a light oil burning scent to the exhaust but
never any smoke and it didnt use any more oil than normal. I've been keeping
an eye on it, expecting it to go wrong and sure enough recently ive noticed
little blue clouds of death pop out when ive been idling at lights for a
while then pulled away (not like the plumes of blue-white that came during
idling when the turbo seals had failed). It culminated in a large plume of
blue smoke when i pulled off my drive after a couple of days rest on. So I'm
fairly convinced thats my problem.

Now then, having diagnosed it I had a nasty thought. The top end is a tad
rattley, and 'something' I havent identified yet rattles fairly loudly (like
tappets) at 3000-2500 rpm. Im fairly sure the shims havent been checked on
it so it may be that. Or it may be the valve guides.

Anyone any good clues as to the likelyhood of guide failure? I'm trying to
decide whether to pull the engine completely, crack it open and do
seals/guides/mains/big ends etc etc or whether to try to keep it as it is
and just do mains/big ends in situ and just do the seals without takin the
head off.

Anyone any experiences? Are guides normally dead when seals have died? On my
old peugeot I replaced the seals but the guides were fine, but then i did
get rid of the car very shortly after so I dont know how it faired.

J