Another exhaust question - 2.5" rams horn

[bhap]

I have a pair of 2.5" rams horn manifolds on an L31 in a 62 C10 with torsion bar suspension. I'd like to find a 2.5" Y pipe to connect a 3" single exhaust. All of the Y-pipes I've found are either 2" or angled - does anyone know of a Y pipe that will work for my setup - center dump 2.5" into a single 3" outlet? The alternative would be to run 2.5" front pipes back to a merge pipe behind the engine and go single from there. Has anyone used 2.5" front pipes from a 64-65 Corvette? They look like they would fit, but I'd hate to have to buy them just to try. Right now I have no exhaust so I'm trying to get something I can install myself without welding rather than trailering the truck to an exhaust shop. Any suggestions appreciated.

[LostMy65]

I'm thinking a muffler shop should be able to build you a y-pipe out of larger pipe.

[Steeveedee]

I had a SHP 327 in my '64 Impala that had 2-1/2" head pipes. They'd be more likely to fit a truck than the Corvette pipes? It was true dual exhaust, though, no y-pipe in sight.