Hi Angelo, I typed in Eico st-70 schematics into Google and got this link
http://www.triodeel.com/schindex.htm there is a crappy picture there, but there was a link to the unofficial Eico website, which might have more stuff. Just try Googling the name, model and schematics in Google Images and you will find something. As far as cleaning i would not soak transformers in any water based solution. Maybe someone else has good way remove dirt from chassis. Oh i think you might get more responses in the Audio section of the forum, Maybe under the DIY section, Logan