hope your have valve springs that can handle say above 480lift as the stock springs will stack up.
Key is if the head is done right , the valve seats and stems are close where one size will only be used. Mine where close to .150 .160with new Aftermarket cam. if a reground mine was close to 180 .190. In USA most last pads are not counter sunk so taller retainer are used. I think Baz said he has a set up thats different but never seen it thats countersunk to use the stock retainers.
To do th lash pattern I just get a ink pen and mark the rubbing area, put rocker in and set lash turn cam a few times and then pull out and adjust if needed.then mark the rocker and set aside and start on #2 rocker. pull out when set. If the stems and seats are perfect only 1 lash pad size is used. if one stem or valve seat is sunk more than it will use a different size.
I usually do this with a empty block and bolt head on using the center head bolts. Doign one rocker at a time so the cam is ez to turn . then you got it all set and everything is good I install the rockers in set and call it good set to TDC then bolt it on block when ready
http://www.spannerfodder.com/the_works_ ... ratios.gif
get a 280zx Turbo or KA hi volume pump