help with 273

For now since it has the 273.......if it were me and I wanted to drive it a little......drop a newer 318 with roller lifters. Say 92 and down with 302 casting heads. Your flywheel will bolt to it, so will the motor mounts and use the pan from the 273. This way you can drive and build the 273 if you like or pick a bigger small block or what ever while your are having fun with the car. Also don't for get that you need to use the older water pump so that you can use the radiator. Newer motors used a water pump that dumps on the other side and requires different pulley's & brackets. Can you post pictures of the motor?