piston one need tdc wen changing he'd gasket

You have gotten the wrong information from your source .. Get some hands-on help with this from a car savvy buddy that's worked on this type engine before or a better repair manual because intake and exhaust pushrods have got to be in the *correct position* .. They are different lengths .. The exhaust pushrod are longer than the intake pushrods .. Furthermore, the rocker arm torque is not even close to 168 lbs .. I sorry but that's just too much work to do only to have the repair fail in the end.