Head work questions

I'm building a low compression 360. 8.5-9.0 compression.
I plan on shaving /milling the heads 30 thousandths. Heads are open chamber 3769974 heads
I'm wondering if I will have any issues with the intake sealing correctly.
Would it be better to remove the dowels in the top of the block and use RTV instead of the end gaskets? Anything else?
Also, I will be installing Comp Cams 901-16 springs. It looks like I will need to replace the exhaust spring retainers. Can I get away with using the stock intake spring retainers?
Thanks in advance for any help.
Ken