Looks like no one available in the 1st gen section knows, but here's the question:

Is the gslse's 13b exhaust manifolds flange to the cats the same angle as the 2nd generations flange? I tried to find even and image of both so I could match them up but can't find any.

I have a 2nd gen motor and exhaust manifold in my gslse and I'm trying to see if racing beats cat bypass pipe will be able to bolt into my setup. Or if do I have to get one welded?

 

I think racing beat sells a header for that exact purpose. Check with them on the phone. I remember seeing that somewhere.