I acquired a factory set of M20K drawings (the envelope referred to in your service manual).  I don't need them all, will sell each serial number set for $15 mailed. These are folded, nice and clean (unused) and quite readable. 25-0002 to 0171 Sold Steve 25-0172 to 0246 25-0247 to 0298, and SN -0001? Sold Jason 25-0299 to 0446 Sold Tom 25-447 to 0612 Sold 25-1000 to 1199  Sold Matt 25-1200 to 1224 Sold, another Mike 25-1225 to TBA  Sold Mike Aero