not sure where the original modulator vacuum line of powerglide attaches onto engine or if it is even useful anymore.. . am installing a 350 (383) stroker and assume it attaches to the vacuum off of the distributor but there is a T at end of the line, with hose for the distributor vacuum but not sure where the end portion should attach.

 

Going back in time......I think as long as the vacuum is ported, and from the distributor it should be, you're good. You will need the modulator working for it to shift, even just a 2 speed.

 

On my 68 El camino, 327 it comes off the intake manifold; there's a port behind the carb and it also supplies the brake booster