Yeah your spot on there mate

if i bought the valve and installed it what would be the worse case senario???

i think that there was many bits that dont make sense. if it had the merc trans there isnt any signs of the mounting position for it. The mounts for this trans sit on the transom plate.

Worse case would be if you don't have the other parts to set it up.

You wouldn't see any signs. They use the same transom plate but there are no mounts on the Merc Trans bolting it up. The tailstock of the trans fits into the transom plate like the B-W and that is all that supports it. Their 9 inchs shorter than a B-W and the case is aluminum so their much lighter. Only thing you might see would be that the motor mounts would have been bolted to the stringers 9 inchs further to the rear. They have a reverse lock out bolted on top of them and the lines are the same as you explain yours.

Ahhh and im running an offshore mount so there isnt any mounts for the back of the engine apart from the mounts on the transom plate. i realy need to post some pics up for you to see just incase i have somthing major missing. im prety good with all this mechanical stuff its just hard when its non standard equipment

Thinking it may be easier for you just to replace the trim pump with the type that doesn't need the lock out valve and be done with it. You would also replace the 2 lines with one line that would go all the way from the pump to the manifold. To acess the line coming in through the transom you remove the manifold on the bottom of the gimble assembly outside the boat. Remove the 2 nuts and pull it down and you will see it connected to the inside of the manifold. Here's a thread about a guy that elimanated his.
http://forums.iboats.com/showthread.php?t=470072

AHHHH HAAAAAA i got a reverse lock out valve and hey presto it fits! your a champion mate it took a bit of elimination but we got there

the old one must have leaked or something and the owner before me must have chucked it

Jim's one of the good guys! He helped me out immensely during my TRS/Velvet transmission restoration/make over last winter. Sending me pics, links and PDF's of everything I needed to know. S#it I even bought hard to find parts from him. Thanks Jim,
Jason

Hey thanks for the good words Jason! I really find enjoyment being able to help out people when I can on here and on other sites I frequent.