Neil...
I have a pressure gauge that taps into the down pipe(s) ..a MATCO tool.
Basically, a pointy stick and a machine steel threaded hollow port nipple.
I gas weld the hole after tests.
I use a KD tools for valve springs.
http://www.mytoolstore.com/kd/kdengi13.html
I do believe there is a special tool for the Merc' heads. I think KLANN make one. Me ? I'm cheap ! KD does fine.
Guide go hard over the years....If you plan on keeping the car for a while, maybe new guides is a good thing, at least good for the comfort of knowing they are new.
To do them is a job for........Mercedes man...well,nearly.
They are a tedious job...
Need a tool to pull the guide retainers, front crank pully bolt.
Need to swing the a/c compressor mount free.( Real nightmare )
Lower the sway bar.
Remove the belts/fan boss.
Remove the radiator.
Best to remove the hood too.
Cover the fenders with thick cloth.
Buy two new oil spray bars while your in there too.... along with new plastic retainers.
You'll need front oil seal/ timing cover sealer/valve cover seals/rags to stuff down the oil drain holes..........etc.
Shouldn't take ....a few weeks !
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