I'm chiming in because I just recently learned something I was unaware of. In the instructions for installing an ATI Super Dampener on my 351C it cautioned to only use T-40 Plus bits when tightening counter sunk screws to attach the dampener to the hub. Using a regular T-40 will not fit tightly and will damage the screw. So much so that later removal won't be easy if you can removed it at all.
So I did of research and learned more about Torx Plus bits. Well lock me in a freezer and call me a Popsicle! I just tried the T-45 plus in the seat bolt fasteners. You know the ones that you used a Allen key wrench to get them out. Either because you didn't know about Torx fasteners and or only had very basic tools in your box. Just went out for s**ts and giggles and tried a T45 Plus on the seat belt bolt. Fits nice and snug! Even tried a regular T-47. It was better than the T-45 but the T-40 Plus still fit better. The Tool# T70P-2100-A is in all likelihood a T-70 Plus. Like a lot of other stuff Ford just loved to make you purchase more tools to work on their products. (Rotunda brand especially).
Just thought I might make others aware of this and save them some misery (and some Torx bit and Allen Key ends).