Hello Loide, I have a question about Chevy automatic transmissions: I recently bought my 71 El Camino and found out that the automatic is pulled over (turns from the 1st to the 2nd very hard (shirt kit?), 3rd gear slips as soon as the transmission oil is warm back into the 2nd and at some point it no longer switches into the 3rd) Since the overhaul of the automatic anyway costs from 700 up, I am thinking about whether I should install a 4-speed automatic for fuel savings. Can anyone tell me which 4-speed would fit and how elaborate an installation is? Any help warmly welcome. P.S. machine is a tuned 350er. Cheers