Pushrod Length Question

I'm measuring for pushrods on my 470 build with solid lifter cam. I've taken the measurement with checking pushrod at approx zero lash with two threads showing on the Harland Sharp rockers. Should I reduce the pushrod size to account for lash. I think the card is around .018" hot. How does that transfer to cold?
I have 9 inch overall length pushrod with plenty of adjustability. I ran them with my trickflows untouched and after taking .080 off of the deck surface. There was enough thread to still meet harland sharps minimum requirements.
I used smith brothers 3/8th .
You should give them a call though.
They're a great company and very helpful.
Clarification.
400 block decked .010, Hughes solid f/t lifters, .662-.674 lift