My driver is an 84 K10 shortwide with the 305 and SM-465. I bought it 10 years ago used with 120k miles on it. It now has 192K miles. Only thing I've done besides normal oil changes and grease jobs is replace the brake pads & shoes, and put a new water pump on. I sure can't complain about that. I've been kind of hoping the 305 would die so I can install the 292 six banger I have waiting to go in it. I'm thinking the 292 will love the 2.73 axle ratios this truck has. They are too tall for the 305, at least using the SM-465. I'm the slowest thing around getting off the line.