Tennessee: Can I Recover A $5,000 “down Payment” On A Private Vehicle Purchase?

Location: Tennessee, USA (Hamilton County)

I agreed to buy a vintage car from a private seller for $25,000 and paid $5,000 upfront, with the remaining $20,000 due later. I have never taken possession of the car.
The seller’s advertisement clearly disclosed that the car has a newer, non-original engine, so I knew about the engine swap before buying it.

The car was also represented as being registered in Tennessee as an Antique Motor Vehicle. After the purchase, I looked into Tennessee law and discovered that §55-4-111 appears to require an antique vehicle to have a nonmodified engine and body.

This raised a concern for me: if the car has a modified/non-original engine, can it actually qualify for the Tennessee antique registration it was represented as having?

The written agreement from the seller says:
”$5,000.00 downpayment towards the purchase of $25,000.00 1946 Mercury coup restored classic. [VIN]. Remainder of $20,000.00 to be paid on or before September 30, 2026.”

I intentionally mention the exact wording because the seller called the $5,000 a “downpayment,” not a “deposit.” I’m wondering whether that distinction has any significance if the transaction is rescinded.
I asked the seller to cancel the deal and return the $5,000. He refused.

I then sent a formal Certified Mail demand letter requesting the $5,000 back. The seller refused delivery of the certified letter, according to USPS tracking.

I haven’t paid the remaining $20,000 and don’t have the vehicle.

My questions:
Does the antique-registration issue potentially give me grounds to rescind the deal and recover the $5,000?

Does the fact that the seller disclosed the newer engine upfront significantly hurt my position?

Does calling the $5,000 a “downpayment” instead of a “deposit” make any difference legally?

If the vehicle doesn’t meet Tennessee’s statutory definition of an antique motor vehicle, does the seller’s representation that it was registered as one matter?

Would this be worth pursuing in Tennessee General Sessions Court?

I have the signed agreement, proof of payment, original advertisement, registration information, communications with the seller, and the refused certified-mail demand letter.

I’m mainly trying to figure out whether I have a legitimate claim before spending money to file.