Bassman circuit question

[Doc Stitches]

Can someone tell by these pics. what circuit this Silverface Bassman is ? There was no tube chart in the head.

I have spent hours on the web trying to find out and none of the Bassman schematics look like mine, at least not in detail. I want to be certain which circuit it is before I make any changes.

It says 50 watts on the back and A66027 is stamped on the chassis.

Transf. # is 606-2 03

Thanks in advance
Doc