Not exactly, with the countervibes i think all were chrome bore sans for the 3400, but i think real late 3400 were chrome as well. I have a 3700 and a 375 pro, the only difference i see is the 375 is a high top, 3700 is standard. Obviously the 3700 in green and 375 in yellow and black. But alot of the newer ones your right yellow= chrome, green = bare
I believe all the super 25s were chrome, but when they went to like 1800 in green was bare and 180 pro in yellow was chrome. So on and so forth. Im sure theres exceptions to the rule
No chrome bore 3400 or 3800. I used to swear I seen a chrome bore 3400 years ago, but I think I seen one with a rebuilt Sunbelt top end on it.
I think you will find a different starter setup on your 375 compared to your 3700. I just noticed not too long ago that the 395 used the older 3400 style starter pulley also.