If you use the ether, don't use the glow plugs. If it won't start using only the glow plugs, spray WD40 into the air intake, cycle the glow plugs, and crank. The WD40 combusts more easily than #2 diesel fuel, but is not explosive like ether. I'll repeat the caution about not revving or loading the engine before it's warmed up, you'll probably gall the piston skirts.
BTW, I've got a 251 that won't start with ether, but I think it's got a main generator short. Cranks very slow, even with jumper cables.