Considering that the valve train is prob. the hardest working part of your motor, with extream preassures, forces and high tempreatures, a poor head/head gasket & valves a overhaul would b a good way to go.... though

Suggest though you get a compression test done 1'st! This will give you a referance point to work from, and once any work has been done, you have an empherical and accurate measurement, to compare back to should other issues arrise.

Make sure you get a (cold) dry test and a (operating temp) wet test done. This eliminates the poss. of worn rings, etc, and wiil confirm any vacume readings/take the guess work out of things.

Suggest if you not a mechanical person, who has the requied knowledge AND tools, this is best left for your 'trusty' mechanic/engineering shop. It (the head) will have to go to the engineering shop in anycase, for valve guides to b pressed into the head, the head skimmed, and a good idea is 2 have it pressure & cracked tested at the same time, for not 2 many more dollars..

Have fun,

Keep 'n touch
Graham