Mike
10W30 is fine ALL year long here. What ever flavor (Brand) you want or like. Use GM EOS for your additive about 2 OZ per oil change. This will keep your cam and valve train happy. EOS is available at your local GM dealer (last I bought was about 15 a quart).
Your Buddy,
Frank
Yes . All replacement pumps are HV compared to the factory piece. You dont want a True HV pump its too hard on the drive gear. I have the hardened race prepped pumps and gears for sale. You need to PM me for a shipped price.
Frank
If you have your cam ground right why get 1.6 rockers? You dont REALLY need to sonic check your block. I have not seen a iron slant block yet that cant take a .104 over bore. Visual on the core shift and bore. Now if you go .140 or more then I would sonic check and hard block.
Frank