The TKX is an aftermarket trans and comes in a Ford or GM flavor. Sounds like you had a bell for the Ford version but had a GM style TKX. Yikes.
He is talking about an OEM TR6060 which is going to be different than any of the TKX's that are available and there is only one bellhousing available as far as I have seen.
Unfortunately, being that it's the only bellhousing option for a Mopar TR6060 that can do a DS starter, it is cast aluminum or nothing. There is a scatter proof QT one for the TR6060, but it is PS starter only and basically just replaces the OEM cast bell.