stick shift transmission upgrade from a 833 good ol Mopar 4 speed, to a Tremec TKO 5 speed, to a Silver Sport Perfect Fit

 My 69 R/T has the factory 833 4 speed, but, I think everyone would rather have an overdrive. I would.

So, the logical step, rom what I've learned so far, is a Passon Performance kit, for 66 % of the cost of a full trans from Passon.... https://justacarguy.blogspot.com/search?q=passon

or a Tremec TKO, but the torsion bar rear mount gets in the way. 

So, if you've converted to a QA1 front end... I suspect, that the torsion bar mount can be removed. 

But, if the ol Mopar you've got still has the factory front suspension/steering, then you'll either need a Passon trans, or the Silver Sport Perfect Fit. 

Because the Passon people have been their own worst enemy from what I've seen over the past couple years, and can't do customer service like is to eb expected from a company you pay over a hundred dollars with. 

The Silver Sport Transmission crew, Rockford Tenn., have figured out how to machine down a Tremec TKO so it fits when the torsion bar mount is still in place. 

A perfect fit trans from Silver Sport costs a lot though, so much no one mentions the number. $9100.  They do have a 8% discount for military

and even though the words are "perfect fit", "it is physically impossible to get the shifter through the 4 speed hump location in a 66-70 B body " said the guy from Silver Sport.   

You'll also need a new drive shaft that will fit the new dimension.

the quote includes a bellhousing for a Tremec to a Mopar big block (1100 bucks) and the Tremec trans (4900 but varies a little based on which trans you select)