I got mine here: http://www.ebay.co.uk/itm/302623785456 The speed triple headlight is 5,75 inch. Not sure what the Thunderbird's size is? But I'm sure you can find something to fit.
Do you like it ? Similar to this one ? https://www.amazon.com/dp/B07BKTV1K...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it JJ
At least yours mentions the bike. Most that I see do not do that. Most mention harley. Some are more powerful than others. https://www.amazon.com/dp/B073VK7FR...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B019ETNZD...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B01EB0AFX...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B01EB0F7I...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B075892T5...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B01DZU30S...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B07FFQFCX...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B074STTM8...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B018LXCV4...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B07BKTV1K...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it https://www.amazon.com/dp/B07G77M84...olid=1ITTTA3VN6HSH&psc=0&ref_=lv_ov_lig_dp_it
As long as you get the size right the make doesn't really matter. Pretty easy to install, too. Mine chuck out a lot of light. And I love the halo's.
