Lude Generation

Before the rocker cover comes off i am looking for info on how to adjust the lifters/tappets
Would they be shims or threaded for adjustment?
Shims is a few hours work whereas apparently another kind of adjustment will only be a half hour job?
Any help appreciated
Cheers guys

Its not shims is a 10mm nut and flat head screw driver. Its not a half hour job though

Thats what my mechanic told me so will see what he charges me
Thanks though that is what i needed to know