I have been offered a recon bw35 box - how do i defo know it is a 35 and is it any different to that fitted to my 1970 3500 auto - it was in a triumph 2.5pi (1969) after being recon but car died. I dont believe i need it ..yet ...but it is readily available to me and I thought worth having but not if it has diff shafts or ratios etc....thoughts...cheers :?