I would avoid the rubber caps, at least on the engine outlets as they
will rupture and usually at the worst possible moment (fine for capping the heater core outlets)
But, you can use this pre-formed "J" hose, Dayco 87617.
(alternate hose-Dayco 87618).
Trim as needed and it works perfectly, looks like it was made just for this purpose. I use it on the race motors.
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