Probably about time-rocker adjustment

So I got my new pushrods today. Melling MPR-155. Put one of the new ones next to the old one and they are a little longer, like a 1/4 inch.. I'm pretty sure they will still work since the adjustable rockers look to have more than that pushing out of the rocker. Since I was going to reassemble with the old pushrods and measure the lash that was set and duplicate it with the new pushrods. Not exact by any means. Or should I do things correctly and remove my intake and timing cover to inspect everything and remove the cam to get a part number to get the correct valve lash and then reassemble? I think I know the answer in my head but what do you all recommend?