I guess, if the filler is at the rear, you could take the handle off to tilt it back.
STRANGE that there is not a drain plug.
Does anyone where you made your purchase know ?
Good Luck, and let us know !
After thought: since you can take and post pictures, Let us see the bottom and maybe we can tell !
Briggs has removed the drain plug from most of there push mower engines. Not even molded into the oil pan anymore. He is correct the oil must be drained through the fill tube. Drain the fuel tank first and you won't have a problem with soaking the ari filter.......I am a Briggs dealer.