Here's the deal, I'm helping a good friend of mine build a '57 Ford truck and scored a free 390 big block Ford. We are using the stock frame. The truck originaly had a straight 6 with the mounts in front of the motor. Any clues to making some mounts that come from the side?
My dad did this exact same swap (390 in a '58 F-100) about 15 years ago and used a mount from Transdapt. Pretty simple bolt in deal..they probably still make it. It wasn't too expensive from what I recall...
I think Speedway also offers a three-piece design for that application. You buy their 390 motor mounts, their rubber isolators, and then the frame mounts for your given application...I think they have frame mounts for a 57 Ford pickup.