Brake line length question

[DroppedMyBuells]

I currently have a pair of MX bars on the bike and recently received the stock clipons from the previous owner and want to put them on; he also sent me the original SS brake lines too. My question is can I use the brake lines for the MX bars when converting back to clipons? The MX bars are a couple inches higher than stock and so the brake line is subsequently longer, so will having a brake line that's a little longer than stock adversely affect the braking? I would rather use a brand spanking new SS line rather than the OEM but if its better to go back to stock I'll do it.
Also, one more question: if I should go back to using the OEM brake line, should I clean it out inside or just put it back on and flush like normal? I ask because the old brake line came with a fair amount of grime on it and I don't want to potentially pump crud through the brake system.
Thanks ya'll!

[user_deleted]

will having a brake line that's a little longer than stock adversely affect the braking?
NO

if I should go back to using the OEM brake line, should I clean it out inside
YES

the trick is to install the line onto the caliper first....then route it up to the master cylinder following the same path as the factory did. when you reach the m/c banjo bolt/line attachment point and determine that you have several inches of excess line do NOT point the line in or out and put a kink/bend in it. simply curl it into a loop them attach to m/c.
your next question will be "how did the factory route the line". google your specific year and model....click image tab....and see for yourself

[DroppedMyBuells]

Super helpful, and you read my mind. Thanks!