I'd go with the 351, as already mentioned you'll need a small block tranny(or maybe just a small block bellhousing if it has the FMX trans).
My build on a driver '67-'69 Bird would be 351/393/408, with a good set of heads and a AOD trans(or C4 if you ain't worried about mpg). Add a mild cam, 2400-2800 stall and 3.50 gear, even the 351 would slaughter any stock 390 and likely give a stock 429 a hard run.
Damn I just notice this was orig posted way back in July..[img]/phpBB/images/smiles/icon_bicker.gif[/img]
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1988 Turbo Coupe...Trick Flow 5.0... AOD... 3.73s
<font size=-1>[ This Message was edited by: TurboCoupe50 on 11/9/05 3:25am ]</font>