Whats the difference between the top three 5 speeds

Ok I just got some prices right from the horses mouth...

Keisler 600 RS 5 speed OD with everything included to go from a auto to manual = $5300

Passon A-833 5 speed OD with everthing included same as above = $6620

A couple of differences with these obviously..

Keisler: Customer has to modify the torsion bar cross member then cut a hole for the shifter... This was alarming to me at first but they said they have a 68 Barracuda in the shop now waiting on the instal and once they fab up the torsion bar cross member it will be included in the package.

Passon: No real modifications if you already have 4 speed.. but if your like me and need to cut anyways that doesn't really matter.

I closing I think the $1300 difference is going to play the largest role in my decision.