Ok please god someone tell me what this motor came out of and what it is. Casting number is 10243880. These numbers came off the front: 1m1108 and 6g35. The head numbers are 14102193. The cam and liters are flat tappet not roller??! From what I've gathered mortec says its suppose to be an 87-up roller but I just looked at the lifters and it is not.

Nvm. I have been informed in the late 80's these blocks came stock with flat tappet cams and lifters however they are already provisioned from the factory to accept roller cams.

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Yes, as long as the block is set up for the roller cam. Look in the middle of the lifter valley and see if there are 3 small upwardly-protruding bosses with threaded holes in them, between the left & right lifter rows. The lifter guide retainer ("spider") bolts to these. Then look at the front camshaft hole, and see if there are two threaded holes alongside it. The camshaft retainer plate bolts to them.
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