OT, but the Cessna's I worked on in Vietnam (Army 0-1) had the 0-470 engine with a bit more HP than yours, but not all of them even had variable pitch props. The DeHaviland Beaver's I was trained on, but seldom worked on had the old R-980 P&W engines. All great fun, and I miss flying still sometimes though I was a mechanic, and not a pilot I did get a lot of stick time. The stick time was to give me incentive to tune those 0-470 engines, and especially the variable pitch props to give the pilot everything he could get when pulling up from a low speed flaps down smoke rocket run. Often the guys on the other end of the smoke rocket run usually didn't want us hanging around putting smoke down for the Navy jets to see, and 45-50 mph seems pretty slow by the time you get close enuough to fire. Here is one I mounted an M-60 machine gun on, and I thought you might enjoy.