No problem, I have not seen many of these in good shape over the years and upgraded to the diesel mainly as I know I can get another diesel from surplus for a backup later on.
The large plug (with glass inset) under the fill height plug in the front center is a gage indicating the oil height I believe. Mine was inoperable so I just check the height with the small plug above depending on use. Under all that paint on the tank data plate you will find the year the tank was made and other info as you can see in my photo (mine is a 1952 tank).
For the drain, I have a pipe elbow, valve and pipe plug for the daily draining they mention to do. I hardly ever have much moisture in mine but it is easy to check with the valve after removing the plug (plug is just for safety in case valve is open inadvertently).
The large plate on the end of the tank held in by 8 bolts or so is where the screen is if I remember right (99% sure).
For HP, taken from a Smoke Stack forum after doing a Google search,
(Paul: A old manual lists a 162 at 58 @3200, Torque 122 @1600. 1800 is in the peak power area. I would guess HP around 40.Tom) seems about what to expect, it will do what ever you want. I run my jackhammer between 85 psi and 95 psi depending on how hard the ground is and it has no problem running all day.
I have data plates (3) on the drivers side front side for pressure settings, (1) on the air tank, (1) on fill plug on tank, (1) under the passenger side front under the valve to charge the system and (1) above near top. Attached are some photos of the data plates below, if you have any other ones not here I would like to see, should be one somewhere for the unit model, year, pump and serial numbers, mine might be there somewhere under the paint if I know where to look.
Starting and stopping: Open charging valve when you start and slowly close to use air, open before you shut off and then turn off engine to prevent engine lock up and oil blowing out of air cleaner.
Original fuel pumps are expensive these days, I installed an in-line electric fuel pump and that cured most of engine stalling I was having at one time as the carburetor seemed to like fuel pressure to it.
Air cleaner is oil bath, easy to maintain, just check from time to time and especially if running in dusty conditions, engine oil should be fine (what I use) or as recommended.
Canandaigua is 20 miles from me, you are about 70 miles, nice looking hose reel.
Good luck, let me know if you have any other questions,