That the best term to look at generally speaking (the best combo of RV and MF), so you are off to a good start.
The keys to getting a good deal on one of these are simple, but not easy (as it will take some good old fashioned digging around).
You need to find a dealer with an LT1 on the lot, or incoming (with a foreseeable ETA).
You need to obtain a GM Supplier code. Beg and plead with anyone to give you one who may have one!
Now…you need to hope/convince the dealer(s) who have the cars to do a GM Supplier deal. Honestly, most right now wont. But, a number of them will. And, some folks have gotten very very lucky and found a dealer to do GM Supplier pricing WITHOUT a supplier code. But, I wouldnt bank on this.
Ideally, youll also find a dealer that honors the sub $75 doc fee that is supposed to be part of the Supplier program. Most wont (esp in FL).
Lastly, and youve already figured this out, you need base MF (or a larger discount to account for a marked up MF).
A sample for a straight up supplier deal at base MF and no dealer fee is linked below.