You need to add shims to get the proper positioning.
Take the rockers and shaft, insert 1 or 2 shims so to get each rocker centered over the respective valve stem. When doing this we suggest taking another head for trial fitting. And if needed a shim can be cut down by using the Dremel and sanding wheel. Add what ever shims (# and/or thickness) are needed for each rocker alignment. Also note that after layouting out the shaft, rockers and shims fit the shaft/rockers on the head and torque it down. Sometimes after torqueing down the shaft the # of required shims and/or thickness may need to be revised as the alignment can change after torque down..

Yes it takes some time to optimize but once done, the end-result will be worth it.


Just my $0.02..