Two suggestions with regard to the head and block milling/decking:
FIRST: Before you bolt everything together it would be worth the effort to measure the combustion chamber so you can calculate your compression ratio. I milled 50 off the head and 50 off the block in my 261 and wish I'd measured everything before I put it together. Once you know the compression ratio you'll know if you need high test or can get by on regular unleaded.
Here's an article with the basics.
http://www.circletrack.com/techarticles/ctrp_0505_comp_ratio/ SECOND: Put some modelling clay on the piston tops where the valves will contact, if they're gonna hit, 1/8" should be enough. Measure the height of the clay. Put the cylinder head on, push rods and lifters in and tighten a couple of bolts and then turn the crank pulley enough for the cylinder(s) you've put the clay in cycle through. Pull the head and check the clay. That'll tell you if your valves will hit the pistons. If they do, you can have the valves recessed in the head and shorten the stems.
