after going thru quite a hassle installing 1.62 springs at 1.93 installed height. how does anyone install 1.64 springs at 1.95 or 2.00 on a iron 906 type head? the 1.62 springs all but touch the body of the rocker. with a standard retainer i had the rocker sitting off the valve stem anywhere from .030 to one that was .050. a set of -.050 valve locks fixed that issue but used up all the installed height. can you mill the spring seat enough to get some installeed height back or am i missing something obvious?