225 Slant Six Oil Smells like gas

when I look at the oil cap on my 68 Valiant I can see moisture and it smells like gas. my fuel pump looks wet with gas on it also. what should I check first? Ive had some people tell me it could be running rich or it could be the fuel pump leaking gas into the engine since the fuel pump is mounted on the side of the motor. How hard of a job is it to change a fuel pump on this slant six?