Hey Neil, one more q if I may. I had my 906 heads shaved .050 to give me a bump in compression for the low comp 400 pistons. I ended up measuring correctly for the smith bros. pushrods and only a full thread or so shows when they are adjusted correctly. Will that .050 be too much to adjust the Crane gold race rockers? How many threads will show with .050? 3 or 4? I am not wanting the adjusters to get out there too far as I was told that is bad. Thanks for all your replies, you are making those old iron lumps look more appealing by the minute.