hi everyone, i got a 78 302 engine in a 86 f250. Supposedly the engine was rebuilt although i would like to check the valve lash. It runs although i'm missing something somewhere. After reading i understand that i need to start at tdc and check/adjust valve lash then turn crankshaft 1/4 turn and go in order of firing. now my question is when i check the valve lash with a feeler gauge it should be around 2.4mm. When i take the feeler gauge should it be on the bottom of the rocker arm and on the top of the valve itself? Or should i check from the bottom of rocker arm to the top of the valve spring? because right now i cant even get .7mm of a feeler gauge in from the top of the valve to the bottom of the rocker arm. after adjusting should any of the pushrod turn or should they be tight?