Welcome to the forum.
I understand your enthusiasm and appreciate your seeking advice instead of blindly following internet misinformation and you have stumbled on the right place.
The TRX200D was introduced fi=or the 1991 model year and was produced through 1997. They wera all Type II with product code HF1. There were two versions; 49 state and New Hampshire. There is no published data indicating a DR model, but the New Hampshire model had the designation of DN.
91 was a 5 speed without reverse - 92 thru 97 was 5 speed with reverse
The VIN will reveal the year model
In 91 and 92; the 49 state model VIN started 478TE174 and the NH model was 478TE177
The 93 thru 97 models were; 49 state 478TE170 and NH 478TE173
The 10th digit of the VIN is the model year: M=91, N=92, P=93, R=94, S=95, T=96 and V=97
I'm going to guess yours is a 93 model
The oil filter is a brass or steel micro screen in the crankcase and a centrifuge chamber on the centrifugal clutch - no paper or cartridge filtration.
Fuel filter is part of the petcock and located inside the fuel tank.
Air filter (if it's foam) is washed in mineral spirits, kerosene or with soap and water, dried and oiled with
air filter oil - I like Uni aerosol oil, a froind of mine swears by Twin Air pour on oil and there are other brands of filter oil available, but they are all applied the same - put on the filter and work the oil into the foam by massaging the oil into the media - when the filter is completely oiled, place between paper towels and blot as much excess oil out as possible - blot by pressing and not by twisting. Install and done.
Finally, you can get a PDF download of the service manual for $15 at
TRADEBIT.COM