I think I have stumbled across a pair of 24v engines that I could put in the Sierra but which should I go for?

The BOA has the engine loom and ECU. The BOB is just the engine (I don't want the autoboxes, though they are still attached) as I will be using my 4x4 box, so know I'll need to use my current sump with oil pickup and two returns to be added.

Neither have run for years and are being sold as seen. The BOB has lost the V6 Cosworth engine cover and I haven't actually seen the BOA yet.

I'm really not that fussed about more power and the economy is neither here nor there.

From what I've read, the BOB is a more powerful and stronger engine but needs the BOA ECU or aftermarket management and I think the seller will mix and match, but how do I get past the thing that looks for the autobox?

Anyone have real-world experience of these?

And what sort of money should I be looking to pay?