I put a 50 Ford on a 76 Olds Cutlass chassis. The whhelbase was an inch longer. I centered the front wheels in the wheel opening. The rear end was too wide so I had to radius the rear wheel opening so you couldn't notice the extra inch. The floor was rusted away in the Ford so I left the Cutlass floorboards on the frame and welded the body over the floor. If you're about to lose your daily driver you don't have enough time to do this before you're on foot.

A Chevy V8 will be an easy swap into your truck. I think you can buy a set of mounts to bolt it in. The problem is the rear end will need to be changed. It has a torque tube driveshaft that won't hook up to any transmission that will fit the new engine. The only quick way to get back on the road is to get another 235 or buy another daily driver.