355 Dashboard lights

All type 74, twenty six bulbs if I recall. It's in the manual to confirm.

https://www.autozone.com/electrical-and-lighting/check-engine-light-mini-bulb/p/sylvania-longlife-mini-bulb-74ll/16841_0_0

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The wattage of the lamps seems to vary
https://www.ferrarichat.com/forum/threads/355-dash-instrument-light-bulb-type-no.513206/#post-144496674

(EDIT: I thought all my instrument panel lamp holders were black and my warning light holders red, but now I'm not so sure. I assume the bulb holder colour indicates wattage. i.e. black is 2 watts and red is 1.2 watts?)

Does the 3rd digit in the lamp holder type mean the diameter of the bulb? e.g. B8.4d = 4mm???

The linked message thread also highlights that the circuit board thickness is a critical factor.

 

Here's another variation (non-F1) (not my car)

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I would have thought backlighting would be black (low wattage) and warning lights red (high wattage) including the warning lights in the 2 central gauges (but the speedo is red in both photos and the central gauge/gauges are both black)

 

SDL lights tend to burn out the fastest as they get the most use

 

(EDIT) Just noticed: I don't know if it's due to the lens used to take that photo, but the reds in the speedo seem bigger than the black ones. If you measure them in the photo, they are bigger.
I would measure the instrument hole diameter and the lampholder diameter. Also measure the thickness of the instrument circuit board if you choose an aftermarket lampholder.