Brake fluid

[Race.it]

Ok, think I know the answer, but just for piece of mind

Today I started to install a new brake system on the 1954, it's a cpp master cylinder under the floor, but unlike the std it's the dual line one.

Now on top of the master cyl it's states use only dot 3 fluid. From what I know I can also use dot 4 or dot 5.1 but should I or do I need to look for dot3

I know in my other hobbie cars I use 5.1 (they get tracked and brakes heat up, but this is not going to get on the track with std drum brakes and not swapping to disks till I do a ifs on the frame.