If you need to adjust the shims (solid lifters) or clearance etc its not as straight forward as saying it has to be this or that. You need to measure the clearance between lobe on the cam and valve when the valve is shut with a feeler blade, find out what is should be and subtract the two figures to get the difference in spec. then either get shims to compensate and make up the difference or adjust the clearance till the correct spec is achieved. If you have to start messing about with shims then it gets quite involved. But if you willing its just simple maths to work out what you need. If you have hydraulic lifters then there is no adjustment they are self adjusting. Ka's are tappy as feck anyway, arnt the early engines based on a 1960's ford anglia engine