I have a 76 superglide (vin 2C) shovelhead 96". At high rpm on highway, my front cylinder intake valve pushrod lock nut came loose and completely shortened the pushrod adjustment. I am about to readjust it and have a few questions. 1) Would a factory valve lifter in this engine be hydraulic and is there a way to tell without removing? 2) There are 2 marks on my crank for timing. One is a circle and the other is a straight line. Which would mean TDC? 3) With my used wet supposedly hydraulic lifter and supposedly factory pushrods, would it be of to adjust this front intake pushrod by adjusting lower nut until it contacts lifter then continue to compress lifter by 3.5 to 4 more turns?