Offset locks to replace exhaust rotator retainers

Valve keeper location with a 2 groove exhaust valve and using a rotator nets about a 1.500 spring installed height in used condition. This is using the non dampened spring for the comparison, seated pressure is 70 lbs. Then take the rotator off and install the intake retainer, still using the 2 (edited) groove keeper set up, you now have an installed height available at 1.600. But the original short stock exhaust spring now needs to be shimmed to rectify the loss of seated spring pressure OR select a spring that would net a sensible seated pressure, (not use the non dampened stock intake spring with the intake retainer and 2 groove valve/keeper combo that nets 120 lbs on the seat).
He can use stock intake springs and retainers with a new 4 groove exhaust valve to accomplish the correct math. Either way it's an 8 pack of springs or an 8 pack of valves.