I would source a used engine, hear it run, do a compression & leak down test, clean it and put new gaskets on it to stop the leaks, then install. Make sure yours is bad 1st. Where are you located? People on the board have multiple parts cars.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.