'02 Outback LSV

I would like to add a shutoff – valve to my boat. It is more for a safety factor then anything else, plus I think it is required now on new boats.

I have looked at Lowes and Home Depot and found a 1.25 valve (don’t recall if it was full flow) and a PVC nipple, have not located a female elbow. From the looks I am not even sure if I can remove the existing male barb elbow without dropping the inlet strainer down for clearance to remove the elbow.

It seems it could be done 2 ways.

1) Splice the valve in the existing 1.25 hose (2 male barb nipples and ball valve)
2) Remove the current elbow start from there (female elbow, close nipple, ball valve, male barb nipple)

I have located a 1.25 ball-valve, and a barb nipple, but it seems I may have to order the rest from various sites. It would be great to get all the parts from one place and know they will connect. I am ignorant about the thread types and those details.

I am looking for some advice and ideally pictures of an existing setup.