Got my heads back today...may have a problem

[82 GT]

I finally got my heads back from the machine shop today. I was suposed to have 2.02/1.60 valves installed but he said they were too close together in the chamber and was afraid that after the guides wore down after while they would end up hitting each other.
He decided to go with the 1.94/1.60 valves just to play it safe.
Well that was ok with me but................tonight I took an old intake valve and set it into one of the valve reliefs on my pistons and noticed the relief isn't much bigger than the old valve(1.78)
Should I be worried about my piston/valve clearance now because the relief may not be big enough or is it really too hard to to tell just by looking?
I bought clay tonight to check clearance but I just got a little worried when I noticed this.
The difference in size between the old/new valves is only .16
Has anyone increased their valve size in a stock head and not have to fly cut the pistons?