Tappets/valve train/top end - here we go again....

[TCGPX]

Also, how difficult should it be to get the feeler gauge between the cam lobe and the roller? They are fairly tight, but it does go in without too much effort and you can move them around.

The feeler gauge is not inserted between the rollers, under the locknut is where you insert the feeler gauge, basically you measure the gap between the valve and rocker, not rocker and cam lobe.

The second quote is taken from bigpitty1's DIY on adjusting your tappets. Not sure if this is where you were measuring shaun, but maybe it'll help.

[bigpitty1]

In the workshop manual it say to insert in between the rollers and the small cam lob which is the correct way and easiest way, I did mine beween the lifter and valve and mine runs really quiet and have no problems but it is difficult to get the feeler gauge in there.

I did it this way to make sure that both valves had the same clearance.