Well I thought I was getting a SD sending unit but when I arrived at my local Mustang parts house they only had one type in stock, the same "modern, high quality" version I've had in my '66 the last couple years. Not sure who makes it but this modern design version is supposedly the best on the market. I went ahead and bought it because I tested it the last time I installed it and the readings are very accurate. I'll test it again when I install the new one this weekend and share my findings.
66 GT350 Tribute in Sapphire Blue built over 12-years and finally being driven!