Pretty much. I didn't believe it either till I mocked up the stock pushrods, thinking I might have to make 'em longer. I then tried to install a stock LS1 pushrod, and with the stock cam it hung the valve open about 0.090". With a gnarly cam grind, stock LS1 pushrod length might actually work. As far as keeping the head casting in the temperature zone, it's just a matter of weld a little, check the temperature, weld a little, check temperature, it's getting close to too hot, wait a bit, check temp, cooling off, weld a bit, ect. Nothing real special but I do use Tempilstick temperature indicating crayons. If I'm doing a cold casting, then I use my hand, the casting shouldn't get too hot to touch. Alloy is a pretty good conductor, so if you aren't doing a LOT of welding, best to keep it cold. If you have to do a lot of welding, get it up to temp and keep it there, minimizing the temperature fluctuations helps to keep the warpage all going the same direction instead of sending the casting every which way.