MK-ll How can I tell?

[standing8count]

I'm looking at a mk-ll and I don't know which one it is.Is there a way to tell by the SN number?Or can I look for some markings on it?
thanx
ROD
S8C

 

[standing8count]

Thank you..but I could not see anything on there that would help.

 

[standing8count]

OK I will an thank you gts.
I'm a little like Fred Flintstone on a computer using a rock to beat the keyboard
Just in case I can't find it this is the SN on one of them i'm looking at(9952)

 

[Bullen]

Well, with that serial#, I would guess it´s a IIB.

 

[standing8count]

I think it is a 1982.Thats what it looks like it says behind the power tubes.

thank you Bullen