To rebuild or not to rebuild that is the question

[truck69]

I have a 69 Chevy Custom Camper C20. As you can see from the picture below I have so far just taken the chrome trim off. I finally have saved a little money and need your opinion. I was going to try to get a deep sound to the muffler system so when I stepped on the gas it would sound great. But my brother said the only way to get that would be to rebuild the engine and throw another cam in it. This truck will be taken to car shows and driving around town..not the drags. Or he said we can take the engine out..put new seals and belts and fix the transmission leak and paint the block. Then throw a better carb on top and some chrome for the air cleaner and value covers and let it go at that. This engine has seen better days but it does run great. Next year I hope to get it painted...new wheels...new interior..sound system...and lowered a bit. Nothing to radical. Would you throw the $$$$ into rebuilding it or just make it look good for now? Any ideas or opinions would be welcomed.
Thanks. Truck69