904 giving up the ghost?

Sorry if I'm being impatient but this car has been down for too long now I'm getting withdrawal from not driving it lol, really want to get it back together before the end of this weekend. Aside from drilling out that tiny 1-2 shift hole to 3/16" what other mods can I do before putting it all back together?

Also can I just check the valves for free movement in the valve body casting and leave it alone or is it necessary to disassemble the whole thing and clean it out?