73 door glass question

[Hertzdaddy]

I need to get the sash channels for the lower edge of the door glass on my 73 Jimmy. I looked at LMC and they list 74 up for the channels. Mine have that little triangular shape piece below the channel but the glass is the same shape as all of the other years.

My question is can I use the 74 up replacement sash channel with my existing vertical channel hardware?

Also, where do I get the felt liners to reline my vertical channels? I see the forward liners in the LMC catalog but no rear liners (just a complete replacement channel).

Thanks.