"Fun" with adjustable rockers and hydraulic lifters

A friend of mine told me something similar over the phone last night. Someone on Allpar suggested shimming the rocker shaft up a short distance. I'm going to look for shims, and if I can't find the kind I'd like then I'll try to find grade-5 washers that have the right inner and outer diameters, which I'll then bend to shape and install... Assuming that the oiling bolt hole will still pass properly...
When people talk about shimming the rocker shaft, there talking about .030 or close to that. Not the thickness of a flat washer. The proper way is custom pushrods.