Mystery solid lift cam valve lash help

I’m gonna preface this by saying I don’t know much about cars. I’ve been fuckin with old harleys for a few years now. This is my first project car. 70 dart swinger with a 383 and 906 heads. It had a tick, after getting the rockers and pushrods out I discovered I have a solid lift cam and stamped steel rockers with a lot of slop in the pushrods. I’ve since then picked up a set of isky adjustable rockers and the correct length pushrods from 440source. My brother and I are going to adjust the rockers using the eo/ic method, I’m looking for suggests on what I should set the lash at on a mystery cam. It hits a pretty healthy lick. Was used as a race car.

184DA2A7-FF61-4FA3-96E7-CE50333C3ADA.jpeg