I put a HiPo 350 w/700r4 transmission in my ‘62 C-10 a few years back. Very easy install using aftermarket front motor mounts (Speedway I think) and a aftermarket transmission mount (also Speedway). Set the engine where I wanted it to live and bolted the mounts to the engine. Marked the location on the frame, lifted the engine back out. Drilled holes for the mounts and bolted them in. Set the engine back in place and bolted it in place. Cut out the crossmember that used to mount the tranny. Installed the 700r4 on the engine and fabricated in the new transmission mount. Installed the high transmission hump along with a Lokar floor shift. Measure for the driveshaft, hookup electrics and accelerator and your there. Good luck.