No changes needed to the fitting. Exactly the same - in terms of physical sizing and fitting #. I got these off ebay from China. I have heard arguments about quality but I try to make the $ go as far as it can (within reason). Some things I won't compromise on.
I know some argue they are inferior but I've used some Chinese boards and such from China etc and they've been perfectly serviceable.
On your point re brightness - Yeah they're just right in terms of brightness really even and I'm happy.
One thing I did find - and this is to do with CAN - one unit didn't come on at first so I thought Oh-O rude word re quality - but no, reversed and it was fine - realised it is the specific contact in the lamp holder. I also found that if you insert them whilst the circuit is hot its a no go. Turn the relevant circuit off and its good to go when plugged in and then switched.
I just looked up the bulb specs from the FSM and then made sure I purchased a lamp which was the same - in this case 3157 T25 P27-7W.
I dug up the Packing slip and they were actually $10 each but sold as a pair so I got 2 pairs posted for $40. With a life expectancy of 50 000 hours - I should never have to do it again given I don't reverse everywhere I drive.
although sometimes I feel so.
Cheers and good luck with the CB. Always something.