Not large enough for a 503. 194,230,250, 292 all look different than GMC engines, although about the same length. GMC valve covers are rounded on top with no length wise marks. Chevies have some kind of lengthwise marks. If it is a 292, the pushrod cover is about 6" high. Show a picture.

Ed
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Last edited by EdPruss; 06/16/2019 4:14 AM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
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