GB,
Those plugs look like AC 43. That's a really cold plug for puttin' around town. In tinkering with my restored '36 Chevy pickup that I've owned since 1965 I've found that with optimum carburetor jetting an AC 46 plug gives a perfect color in short drives around town, like over to the park for a picnic lunch with my wife. If you PM me your email address I'll send you a plug color photo I just took for comparison purposes in before and after my PCV fabrication.
As Tim points out those compression pressures are not good, as is the "bouncy" vacuum gauge reading. There are online tutorials showing you what various vacuum gauge behavior tells you about your engine.
An easy valve and ring condition test can be done by making a fitting to go in the spark plug holes and pressurizing each cylinder with compressed air with both valves closed. Then listen at the exhaust pipe, carburetor throat and draft tube outlet for leaking or burned valves or severely worn rings/bores. That technique is below low tech but it sure works!
Good luck!
