Ok the clock is running nicely, even with-it being way over on the other side of the board!! Not all ICs are in yet but I'm assuming I'm going to have issues with noise once the board gets busy.

Have also installed the reset circuit as per below with a CMOS Z80 the circuit doesn't work. I think it is due to the mix of TTL and CMOS. The reset circuit using purely 74LS caused the /RESET line to stay low. I replaced the 74LS02 with a 74HCT02 and it fixed the /RESET staying low but the reset button doesn't work. Need further investigation but probably need to replace IC2 with a 74HCT as well. Need to scratch around to see if I have one else I guess I could put a 1k pull up on the /RESET to ensure there is +5v on the line.

Also getting some nasty spikes on the data and address lines, this CMOS/TTL mix is going to be an ongoing problem me thinks.