273 Comando - What's it worth?

We pulled the High Performance 273 out of the 'Cuda this past weekend. I have a rebuilt 340/727 ready to go in when the car gets out of the paint shop. A friend expressed interest in the 273/904 combination. I wasn't really sure what to ask for it. The engine is probably not the original for my car. The fender tag calls for a standard 273, not high performance. I guess someone might have added the 4-barrel intake and valve covers to the original block, but I'm not sure. Anyway, the tranny is good. The engine burns oil at a pretty good clip. We replaced the valve seals last spring, but that made little if any difference. I was going to rebuild it this winter. The guy who wants is a Ford mechanic who just bought a '71 Dart, and would rebuild it himself. What do you think the combo is worth?

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