Also a lifelong mechanic I can ID most transmissions from sight. I just sold some 1970's 350 turbo cores. One long tail and two short tail to a local rebuilder. Got $25 bucks each without converters. Even with the long tail 350 being rare it's still just a 350 turbo core. I do get more for heavy duty 3 speed 400 turbos out of trucks. Around $75. They have extra clutches etc. and are desired for heavy duty use and offroading however the L60 trans group are overdrive lock up converter transmissions and just as heavy duty as the 400 Hydro making them more valuable for cores than the non OD transmissions. I have found that transverse transmissions have sme value. I sold a 90's Honda Accord automatic core the other day and got $100 out of it. I did find out recently that early 350 turbos with the universal bell housing to fit both Chevy's and Buicks,Olds etc. are in demand and are rare. They came out back in the 70's when GM cars at the end of the year ran out of the correct engines for the application so they substituted what they had from other brands. Some Olds cars came with Buick engines and visa versa Buicks and Olds cars with Chevy engines making the need for a universal bell housing pattern. Maufactuers can't do that switching around stuff anymore. Risk of to many lawsuits from consumers not getting what they paid for.