Getting ready to change to a deeper trans pan and noticed the filter extension does not have an o ring like the one I took off. Is that gonna make any difference?

So the one on the left is the one you are going to use ?.....

I would make-up a quick gasket. It could suck air if you don't use something to seal it.

Good thing you're chucking that aluminum pan for the superior steel one!

Was just going to change oil n filter but had the cast on the shelf but don't want to take a chance on the trans losing prime. Probably why I got a good deal on it!
Probably stay with the steel.

hardly think that thing will lose prime using the spacer you have. Probably run it around the "add" line. My dad had one of those aluminum Summit pans on the Duster when I got it. Got one of the lucky ones that leaked, even with the reusable gasket. I swapped it out for a 47RH pan I had laying around. I do miss the drain plug, but could add one to the steel pan I suppose.

Some used a gasket in earlier designs.....If u cant locate one ,i've made em....
http://www.kmjent.com/cart/images/P/MOR42080.jpg if u feel u want an o ring... http://www.summitracing.com/parts/der-14010/overview/