Im prepping my 89 TA for paint and thinking about pulling the w/shield to do a better job. My question is,can I get the black plastic trim around it anywhere?

 

Any auto glass shop will be able to sell it to you by the foot. I'm pretty sure it is just 1/2" "T" push in molding.

For the price of a windshield, I would cut it out before you paint the car. The thin window edge trim can allow water in over time and cause a rusty window frame. I used to install auto glass and seen this happen many times.