I have a brochure copyrighted 1964 that I presume is for the '65 model year which lists the 600-T and the 440-T. The receiver chart is from the 1967 Fisher Handbook. So I suppose it's possible the 660-T could have been from the 1966 model year.
I recently acquired another Fisher Handbook copyrighted 1968 which has a price list effective Dec. 20, 1968 so it should be for the '69 model year. It covers the 160-T, 175-T, 200-T, 250-T, 400-T and the 500-TX receiver-wise.
I also have a copy of A Technical Analysis Of All Fisher Receivers And Speakers that the good folks at the Smithsonian scanned for me. It's copyrighted 1970 so should be the '71 model year. It covers the 202, 250-TX, 250-TX, 500-TX and the 701 receiver-wise.
Then there's the somewhat trashy '73 catalog which actually identifies itself as being from that year right on the cover. It covers the following receivers: 170, 180, 203, 205 and the 801. That's as far as I'm going to go since they appear to be getting somewhat marginal at this point.
So I basically have solid state component information for every other year from '65 to '73. I could use help with '66, '68, '70 and '72 which will probably be copyrighted '65, '67, '69 and '71.