Personally I would definitely convert the marquee lighting to TL.
The incandescent lighting is very energy inefficient (50 watts compared to about 18 Watt), it has a very uneven light on the marquee AND gets pretty hot compared to TL.
For some weird reason (probably saving a couple of cents in production costs) Bally-Midway changed the lighting from TL fixture to those two stupid incandescent bulbs during the production of Galaxian (mine is early enough to have the TL) and I'm sure the same thing happened with Pac Man.
Luckily they changed back to TL during Ms. Pac and Galaga again (I bet the ops complained about it).
Just my opinion of course....