Hi Charl,
I wrote up a proposal to sink 17 old shrimpers down here in the Sea of Cortez near Loreto a few years back, on some of my Seamounts that I have found over the years. Each one of these mounts are a great dive by themselves, then add a sunken wreck, and in a couple of months you have fish schooling all around them, and they are really eye openers.
You could do the same in a smaller scale, even one small vessel is quite a magnet for palagic fish, since they attract the smaller local fish. You would be surprised how much action you could get out of a small boat in the 20 to 30 foot range, and some marinas have a few junk boats they would like to get rid of. The cleanup takes a little time, but the results can be awesome. Just remember to leave surface clearance, so they are not a hazard to vessels transiting the area. The drop is what takes a little planning, you don´t want it to land upside down and have to use lift bags to roll it over....a real pain.
Good Luck on this. The effort is worth it, Keep it in the green, Terry Kennedy