Originally Posted by 2x1foo
I think if you depressed the springs (and valves) at TDC enough to replace a shim, the valve would hit the piston. There is very little clearance there hence the dishes cut into the pistons so the piston doesn't smash into the valves. Perhaps this is doable at 180* of TDC but you will still have to be carefull with the little valve keepers not moving out of place.
It really is quite easy to R&R the rocker shaft. With the valve cover off, I could change a shim in <10 min.
so those 4 top bolts out and the 2 cover caps (on the backside of the pic) and the rocker shafts pull out from the backside of what we see in the pic? rockers moved out the way & then
replace with the proper calculated shim and reassy? actually that seems very simple compared to some of the OHV jap stuff.