I have a 68 camaro now equipped with a 396/TH400 combo that was originally a small block 4 speed car. The conversion from a small block to a big block powerplant made access to the original small block heater inlets nearly impossible, so the owner chose to deprive himself of the luxury of a heater. Now serving as a daily driver, however, the car will be needing a functional heater for this winter. I have seen instances where owners in a similar situation have, instead of replacing the box and heater core with correct big block equipment, have flipped the core over, re-routed the hoses away from the engine, and cut appropriate holes in the heater box as needed. Is this a 1. effective method of heater core surgery, 2. leak-proof solution, and 3. project that would be easier than buying an entirely new heating system? Any suggestions, recommendations, or experiences related to heater core surgeries such as this are greatly appreciated. Thanks.