Here is the left side (DS) of the emergency brake cross member.
Originally it was riveted to the inside of the frame....up at post #5 I detailed blowing out the 4 rivets and replacing them with bolts for two reasons: Ease of installing the longer T5 and to reinstall it under the frame later to clear the T5 and retain the 1965 Ebrake assembly in near factory form - total factory function.
As you can see, the xmember rests on the underside of the frame and the spacers only serve to prevent crushing it as the bolts are drawn up.
With this simple reposition, the gap between the new T5 and the original 1965 Ebrake mechanism is large enough to comfortably stick my hand into...plenty of room.
I have a factory style Walker Head Pipe, single exhaust. Here on the Left (Drivers) side, a slight mod to the ebrake cross member to maximize exhaust clearance. Simply shave off the flanges on the cross member yielding over an inch of clearance between exhaust and cross member.
And on the passenger side? Simple, bolt it back up with a couple of spacers, adjust the ebrake as needed and yer truck won't roll away.
As you can see, with the Astro Van T5 (S10 tail housing) and as Ol Bleu discovered with his S10 T5, NO Need To Go To A 1966 Ebrake Assembly. Use whatcha got. Betcha it'd even work on some of them crazy lowered trucks. Amazing, folks are lowerin em as much as an inch or two these days.