Thanks all for the advice. I just recently decided to return the muffler itself to pep boys and buy the full cat-back system from Jegs online. Going with Dynomax, still, #17493. Turns out that Dynomax has a mail-in rebate deal on their cat-back systems--$75 rebate! So for only $125, I'm getting the full cat-back exhaust. I'll worry about custom tips later, once I know for sure what size tips can fit.
Anyway, for the time being, I've uploaded a video of what the car sounds like without a muffler installed. Enjoy, and thanks again for the advice!
1985 TA, No Muffler