Here's what I did to make S10 151 rear sump pan fit a 153.The rear cutout for the main was too large to fit a 2 piece rear main seal 153.Reduced diameter with sheet metal and braze.The S10 pan held three quarts on the 153 if I wanted the oil level a few inches below the crank throws.more sheet metal, braze, add about a quart.The side and front pan rails fit ok,some bolt holes needed a slight file egging to get the bolts lined up.And the area directly over the oil pump got a little hammer massaging so the pan didn't touch the pump.A Chevy 250 pump pick up reworked to fit my engine.153 pan gasket side rails and RTV sealant only on the front and rear.The two front bolts fastening the pan to the timing cover were omitted like on the 151. The pan is solid hillbilly job that doesn't leak. The header was another fabrication done without much concern for a fine finish. 230-292 header flange, left over bends from a Chevy V8 header kit. And my MIG welder was causing issue,so some of it was gas welded.....It works...
