Hi, the exhaust valve guides aren't in bad condition, but i will get them changed for piece of mind along with the inlet ones. The inlet guides are the worst and are slightly bell mouthed, but the valves themselves measure ok and are in spec. Where are you based and what would be the cost of the valve job?
Regarding the voluming of the chambers using a syringe, i guess this is done after the head is skimed? Does there need to be two holes in the perspex to allow the air out as the water enters?
Thanks lee