That bus has waaay to much style !
It'll be something unique.
What are your plans for the 'Old Bird ? I'll be following your build. Very cool.
Any idea what battery was in there before? Sorry I can't help more.
Update your sig with bus specs/location when you get a chance.
wiki says:
The engine was further enlarged for the 400.7-cubic-inch (6.6 L) 401. It has a 4.87 in (124 mm) bore and 3.58 in stroke (90.9 mm), and was produced from 1960 through 1972. The 401 being a Magnum engine produced 205 gross horse power at 3200 rpm and 377 gross torque at 1400 rpm. This engine was used in the 4000 series and larger trucks.