Please use the 'Go Advanced' and (on the second page) the 'Manage Attachments' buttons to post images. Posting them as you did causes the image to open in a new window. If someone is replying to your post and in the middle of a (possibly extensive) reply they click on the image to confirm something for the post, all text that they typed will be wiped out. For some, that will be enough for them not to reply or to post a much shorter reply. I try to copy all text before I click on an image to prevent the loss in case the image wasn't posted properly. Others should do the same but may forget to do so. Please use the method provided by the forum to post photos in the future.
The bias transistor was on the MEHSA insulator and connected to the board via J200. See attached. Different but very similar to your amp. The arrow shows the bias transistor.