Did you upgrade the oem valves and guide or left the oem? I took my heads to the machine shop to cleaned them, they told me the valves still good and working fine. ill probaly buy a Coml23 compressor tool and install the springs and retainers myself to save a buck, im between ferrea(too expesive for a damm spring and retainers kit) or gsc, thing is i dont know if is worth to change the valves and the guides, not planning to port, just to refresh and polish the intake and exhaust port, and obviusly im upgrading the cams as well. We'll see, for now the heads is not the biggest priority. Main priority is getting the pre built closed deck block. My oem block still good but i think itll be more expensive to build it, specially if I sleeve it or do a closed deck conversion.