drop the hose down to the barb and plug the top one

That tube looks like it is maybe pressed in. Get it out of there and drill and tap it for 1/2NPT and plug it like the one next to it or put a pressure gauge there. The drill size is on the TAP itself.
T.J.

That tube looks like it is maybe pressed in. Get it out of there and drill and tap it for 1/2NPT and plug it like the one next to it or put a pressure gauge there. The drill size is on the TAP itself.
T.J.

yeah but i dont wanna fuk anything up on removal, never did that, nor a tap job(haha) no pun intended of course 

just get like a 3 inch piece of heater hose (either 5/8 or 3/4 cant tell from the pic) and slip it on the end coming out of the manifold and hose clamp it on then put a big bolt in the other side of the hose. Hose clamp that bitch and your done.. ive beed drinkin, hope it makes sense haha thats what u call a quick fix, actualy its how my boat is too

Any decent parts store will have a "made for that purpose" rubber cap. Standard fare for multi use water pump applications. Different year vehicles had different heater hose systems, but basicly the same water pump. So, the rebuilders reduced inventory and supplied that cap to cover different applications. Maybe in the "help" product line isle. It just looks like a large vacuum cap....."A piece of heater hose and a BIG BOLT!!" c'mon, this is a boat, you can't be doing $hit like that on a boat!! Not in plain sight anyway!!!!!! .......MP

I'm using one of the rubber block off caps on the front of my BBC manifold.  The only problem is they seem to deteriorate quicker than regular heater hose, so you have to replace them every season (look for cracks).

get the manifold off and bring it over to pops this weekend and we will get it out and tap it for you

There you go Prospect, even after you bailed on him, Ralph is gonna hook you up.

thanx ralph! yeah ill do that for sure...sorry about sunday, i felt like shit all day dude, ill make it up to ya...

how's sunday sometime?

sounds good, around noon or so

That tube looks like it is maybe pressed in. Get it out of there and drill and tap it for 1/2NPT and plug it like the one next to it or put a pressure gauge there. The drill size is on the TAP itself.
T.J.

This is what I did. Worked out nice. Also whenever possible use aluminum fittings and plugs. Brass on aluminum corrodes faster.